IT'S FEBRUARY 15, 2000, a pivotal moment in the race for the Republican nomination for president, and at the televised candidates' debate in Columbia, S.C., temperatures are rising.

John McCain, fresh off an upset victory in the New Hampshire primary, has run into a buzz saw of negative advertising about his record and rumor-mongering about his personal life, and he blames his main opponent, George W. Bush.

"You should be ashamed," a tight-lipped McCain scolds Bush.

Bush has his own beef: McCain's ads have likened Bush's character to that of Bill Clinton. "You can disagree with me on issues, John, but do not question -- do not question my trustworthiness."

". . . You're putting out stuff that is unbelievable, George, and it's got to stop," McCain retorts. ". . . This is probably the nastiest campaign that people have seen in a long time."

". . . Listen, you're playing the victim here," Bush shoots back. "Wait a minute, remember who called who untrustworthy."

Six years later, Bush is president and McCain is preparing for another run for the White House. He's in Michigan on a Friday afternoon at the start of a long weekend of raising money for local Republican candidates and laying the groundwork for 2008. And everywhere he goes, he's got only good things to say about George W. Bush.

He praises Bush's steadfastness on the war in Iraq and says he's especially proud of Bush's support for the Senate's immigration bill. "I think the president has shown a lot of courage on this issue," he tells a crowd of activists at Kent County GOP headquarters in Grand Rapids, many of whom seem a lot less certain on the matter.

So, what's changed since 2000? someone in the audience asks McCain.

"My personality has improved significantly," quips the senator from Arizona. "I took a Dale Carnegie course."

Then, more seriously: "I think it's very clear that then-Gov. Bush had the support of the Republican establishment. He worked hard for it, and he gained it, and he deserved it." Leaving little doubt that McCain would like to accomplish the same thing himself this time around.

He's no longer offering himself as the alternative to Bush. Now he's positioned himself as Bush's heir, a turnaround that makes some people, including McCain sometimes, more than a little uncomfortable.

Such is the case when McCain pays a visit to "The Daily Show With Jon Stewart" a few weeks later. McCain's almost a regular here, and Stewart usually treats him like he's Abraham Lincoln without the whiskers and the stovepipe hat. But tonight Stewart badgers McCain about Bush's claim that he has made the world a safer place. "My question to you is simply this: How much safer can the world afford to have him make us?"

McCain rolls his eyes. He makes a joke about calling in his lawyers. He hems and haws to the point where Stewart pleads, "Don't dodge the question!" But McCain continues to do exactly that. Finally, Stewart relents. "We're gonna come back and talk about other things," he says at the break.

"Thank God," says McCain.

DON'T LOOK NOW, but 26 months before November 2008 the race for president has already started. McCain and his potential rivals are out on the campaign trail virtually every week. They are raising money and support for federal and state candidates in the 2006 election. But they are also collecting chits, building name recognition and garnering backers for the presidential campaign to come.

"Teddy White must be turning over in his grave," says John Weaver, McCain's chief campaign strategist, referring to the late author of The Making of the President books. "I can't believe we're doing this so early."

But doing it they are. And no one more assiduously, nor with more apparent success, than McCain, who has vaulted to the front of the GOP field. Early polls indicate he gets twice as much support as any other likely Republican candidate except Rudy Giuliani, the former mayor of New York City, who runs close behind. Even in liberal, blue-state strongholds such as Massachusetts, McCain runs even with or better than the two most recognizable Democratic names, Hillary Clinton and Al Gore. As a former Navy pilot who was shot down over Hanoi and spent more than five years as a prisoner of war, he's got impeccable military credentials and stature, and a reputation for bipartisanship and fierce independence that appeals to a broad spectrum of voters. He's also got star power: Turn on your television most days, and you'll find McCain on one of the morning talkfests or on "Larry King Live," "Imus" or "Hannity and Colmes."

Many of the Republican professionals who once wrote off McCain as the loosest of political cannons say they are surprised and impressed at the careful, disciplined way he and his staff have gone about establishing his as yet undeclared candidacy. He is laboring hard to become the presumptive candidate for a party that almost always nominates the presumptive candidate.

"He's very much where George W. Bush was in 1998 and '99 -- getting his team established, trying to create that same air of inevitability that Karl Rove tried to create around Bush," says Saul Anuzis, chairman of Michigan's Republican Party, referring to Bush's political Rasputin.

Still, there are many rivers to cross before November 2008. McCain has to vanquish a formidable cast of possible Republican opponents, which could include Sens. George Allen (Va.), Sam Brownback (Kan.), Bill Frist (Tenn.) and Chuck Hagel (Neb.), along with Newt Gingrich, Giuliani and Massachusetts Gov. Mitt Romney. He also faces a host of enemies among Republican interest groups and social conservatives who have not forgiven or forgotten his run as an iconoclastic insurgent in 2000 and who dislike some of the positions he currently holds on litmus-test issues such as the gay marriage amendment (he's against it) and stem cell research (he's for it).

To succeed, McCain must perform the old political two-step: Capture conservative Republican loyalists who dominate the party's nominating process; then, once nominated, swing back to the center to attract independents and moderate Democrats. It's an especially tricky task for a politician who has always cast himself as a man of unvarnished principles and straight talk.

McCain concedes he's being more careful with his rhetoric and off-the-cuff comments. Which is why he looked so uncomfortable with Jon Stewart: "I don't want to say anything that I'm going to be hearing about for the next couple of years."

Otherwise, he insists, nothing's changed -- except perhaps the perceptions of some analysts. "Some on the liberal side say, 'Ah, McCain's not the maverick that we thought he was. Oh my God, he supports the war in Iraq! How could he!' And some of my friends on the right say, 'Well, he voted against the marriage amendment,'" which would ban gay marriage.

In many ways, he's still the same sly, sardonic and self-deprecatory candidate who charmed the press and a surprisingly large segment of the public in 2000, the quixotic reformer whom political columnist Joe Klein described as "a man on a white horse attempting to traverse a muddy field."

But he's more guarded, more deferential to Bush and all the president's men, more inclined to emphasize his old-fashioned conservative credentials and to downplay those progressive ones. There are fewer confessional moments and even fewer incendiary ones. The man who says his favorite president is the roughriding Theodore Roosevelt sounds more like another military man who became president, the cautious elder statesman Dwight Eisenhower.

Even so, McCain still revels in the spotlight and the sheer giddiness of public life. "The next day after 'The Daily Show,' I walked into the building and, I'm not exaggerating, 100 interns told me, 'I saw you on Jon Stewart!'

"You gotta walk the tightrope," he says. "Life's too short to do it any different."

HE BOUNDS UP THE STEPS of the small Beechjet 400A and pours himself into a leather seat. "This is gonna be a fun trip," he declares as the plane prepares to take off for the Michigan trip. He launches into an analysis of Michigan politics, sprinkled with conversational detours to South Africa in the 1980s, a new book he's reading on the Iraq war and the trials and tribulations of the Arizona Diamondbacks.

McCain turns 70 on Tuesday, and his thinning hair is snowy white. The angular baby face of his Vietnam-era photos is now a full moon with a smooth, doughy chin the color of Pillsbury flour. Two angry red scars plunge down the left side of his cheek in front of his ear, mementos of melanoma surgery in 2000. While they are striking, they seem to fit the biography and the aura. It's easy to imagine that they were inflicted by his North Vietnamese captors, not by a cancer surgeon.

His shoulders are stiff, and he takes aspirin for the pain. He boasts that he's been written up in orthopedic medical journals because his arms, broken when he ejected from his crippled fighter jet over Hanoi in 1967, were left to heal on their own without proper treatment, making him something of a medical phenomenon.

He leaves on his crisp blue blazer even in the privacy of the small plane, and he doesn't loosen his tie. Later, when it's finally time for the coat to come off, he turns to Weaver, who gently pulls the jacket from his shoulders. "Easy, Johnny," McCain hums softly. "Easy does it."

The schedule can be grueling, but Weaver tries to ensure that, except when McCain does the morning talk shows, the senator doesn't have to rise too early or stay up too late. Still, like any canny road warrior, McCain knows to catch a quick bite to eat or a few minutes' sleep whenever the opportunity arises. On this flight, he goes from full-bore conversation to a wispy snore within minutes, his eyes concealed behind a pair of opaque, wraparound Ray-Bans. But even when napping he doesn't seem to miss much.

So how long have you two been traveling together? I ask Weaver after McCain appears to have dozed off.

"Too long," a suddenly wide awake McCain interjects with a crooked grin. "Much too long."

WEAVER, 45, is a lanky, laconic campaign veteran who first joined McCain in 1998 after working for candidates in his native Texas. He says he loved the loose, improvised nature of the 2000 presidential run, yet always feared it was doomed. "Crusades are easier than structured campaigns," he says. "You have less responsibility and more freedom. But you always lose in the end."

When McCain began organizing his 2000 race, he had 3 percent name recognition and virtually no treasury. People vaguely knew his biography -- that his father and grandfather were Navy admirals and that he himself was a Vietnam War hero. He had come home from a Hanoi prison to a hero's welcome in 1973 and landed a job as the Navy's liaison officer to the Senate, where he studied national security policy at the foot of masters such as Sens. Scoop Jackson and John Tower. He also divorced his first wife, Carol -- in one of his many acts of self-confession, he has admitted he was unfaithful -- and married Cindy Hensley, whose politically well-connected father owned Arizona's largest beer distributorship. McCain moved there to seek political office. He won a congressional seat in 1982, then was elected to Barry Goldwater's Senate seat in 1986 when the conservative icon retired.

His political career was nearly derailed by scandal a few years later. McCain was the sole Republican among the "Keating Five" -- senators accused of intervening with federal regulators on behalf of Charles Keating, an Arizona savings-and-loan magnate whose financial failure in the late 1980s cost tax-payers $2 billion. McCain was cleared of wrongdoing by a Senate investigation, but he was deemed to have used "poor judgment." He calls his involvement with Keating "the worst mistake of my life." Afterward, he emerged as the Senate's most ardent champion of campaign finance reform.

McCain says he didn't really think about running for president until he'd finished campaigning for his friend and GOP nominee Bob Dole in 1996. He says he simply believed his military and political experience made him the best-equipped candidate to restore America's confidence in its public institutions.

By 1998, he was ready. Besides Weaver, he hired another veteran Republican operator, Rick Davis, to be his campaign manager. Both men had had run-ins with Karl Rove and the Bush political machine, and each was intrigued by the challenge of going up against it. McCain's campaign had only one asset: a spirited, experienced candidate with a large store of foreign policy expertise and the ability to think fast on his feet.

"Every presidential campaign has to be designed around the candidate," says Davis. "You can run for dogcatcher, and nobody will ever know who you really are. You run for president, and you are stripped bare. Those klieg lights are so bright. So we just built it around John, who he was, what he was."

To underline who he was, McCain and his longtime chief aide, Mark Salter, wrote Faith of My Fathers, a stirring yet self-deprecatory account of his life and times that emphasized the McCain family tradition of military service and patriotic sacrifice. Most campaign biography books die a quick death. Faith of My Fathers, which appeared in 1999, was a bestseller.

With little money to buy ads, Davis, Weaver and company concentrated instead on earning their ebullient candidate lots of free coverage in newspapers, magazines and on television. "We knew that John could carry on a conversation with any reporter for 24 hours a day," says Davis. "So we based our whole campaign model on 'earned media.' If a reporter wanted to fly with him or get an interview, we'd say: 'He's going to the West Coast. You can sit next to him on the plane; you can have the hotel room next to his; you can be in the car with him the entire time.'"

The same strategy produced the campaign bus, dubbed "Straight Talk Express," in which McCain, positioned in a red leather swivel chair like a prime minister, held a running all-day news conference for the media pack. All of it was on the record, much of it lively and self-lacerating.

"This was not the model of choice," says Weaver. "It was the necessity model."

There were times when the unexpurgated McCain drove the staff crazy. Weaver recalls early on in New Hampshire when a textile worker at a town hall meeting expressed concern that his children wouldn't be able to work at the local mill because foreign companies were taking away jobs. "John told the man frankly that he hoped he had a higher ambition for his children than to be textile workers. Salter and I just got up and left the room shaking our heads" at the bluntness.

When McCain beat Bush in New Hampshire by 19 percentage points, the Straight Talk Express became the hottest ticket in mediadom. Television news anchors and media executives vied with working journalists for seats. McCain's staff had to organize lists of reservations like the maitre d' at L'Escargot.

The wheels came off in South Carolina. The Bush machine and its legions poured millions into the campaign there. Anonymous fliers claimed McCain had fathered an illegitimate black child with a prostitute, that he was mentally unstable because of his POW experience and that his wife, Cindy, was a drug addict (she acknowledged she had become addicted to painkillers for a time after back surgery). Republican interest groups, angered by McCain's championing of campaign finance reform, targeted him as well.

"What happened in South Carolina was as bad as people say, and then some," recalls Sen. Lindsey Graham, a Republican from the state and one of McCain's best friends in the Senate. "Every group in the country who makes money off politics declared war on John McCain."

After his defeat, McCain journeyed to Virginia Beach, home of televangelist Pat Robertson, one of his right-wing critics, and denounced Robertson and fellow Christian conservative Jerry Falwell as "agents of intolerance." Riffing to reporters on the bus the next morning, McCain joked about battling "the forces of evil." It was the supreme moment of McCain's insurgency: the maverick white knight tilting at the legions of religious bigotry. Many left-leaning commentators applauded his audacity. But Republican voters were less enthralled. McCain defeated Bush in Michigan and Arizona. But social conservatives and mainstream Republicans handed him defeats in the Super Tuesday primaries in nine of 13 states, including California, New York and Ohio.

The insurgency was over.

"YOU LEARN," SAYS MCCAIN, recalling the bitter lesson of his 2000 defeat. "You really do learn." He's sitting in his senatorial office on a quiet afternoon, his black loafers leveraged against the coffee table, contemplating his evolution from caped crusader to putative front-runner. "One of the things that happened in South Carolina is that I became angry, and I let my anger show. It got me off message, got me kind of off stride. And people don't like that. What they care about is what you're gonna do for them as president of the United States."

At first, he seemed crushed. He told friends he would never run again. Cindy dragged him off to Tahiti for an enforced break. "It felt wonderful to wallow in self-pity for 10 days," he recalls. "But that was enough."

Upon his return, he was surprised to discover that rather than condemning him to oblivion, the defeat had enhanced his national stature and name recognition. He increasingly became the go-to senator for television commentators on foreign affairs and military policy. After the 9/11 attacks, McCain seemed to pop up even more often on news shows, offering words of comfort and determination. He became so popular with independents and many Democrats that Democratic nominee John Kerry tried to persuade him in 2004 to become his vice presidential running mate.

His relationship with Bush has been a work in progress. Both sides say the mutual hostility of the 2000 campaign began to dissipate after McCain and Bush met in Pittsburgh later that spring and agreed to work together. McCain dutifully campaigned for Bush and other Republican candidates. "The relationship has grown warmer over time," says McCain. "We get along very well."

The strategists have followed the lead of their bosses: Weaver says he and Rove sat down for coffee in 2004 and put aside their differences. McCain's camp has already signed at least two of Bush's former operatives for the battle to come.

"You're dealing with people who are professionals," says a senior Republican official with close ties to the president. "Everybody in Bush world understands the most important legacy this president will leave is in dealing with the war on terror with moral clarity. And there's been no more steadfast and articulate proponent of that central policy goal than John McCain."

McCain himself notes that there are several areas in which he continues to disagree with Bush, but even there he tends to make allowances. Last year he pushed through an amendment explicitly banning torture of terrorist suspects that Bush opposed. Bush signed the bill but issued a "signing statement" leaving him the option of waiving the ban when national security is at stake. McCain says he's not troubled by the statement because Bush has personally assured him he will enforce the law.

Recently McCain was among seven Republican senators who voted against a constitutional amendment banning gay marriage and was among 19 who voted for federal funding for embryonic stem cell research, both of which put him at odds with the president. He frequently chides the administration for poor planning and execution of the war in Iraq. But on the campaign trail McCain takes pains to pay homage to the president's "courage and commitment" in staying the course both on the war and on supporting immigration reform.

His staff insists these statements are not the result of political calculation. In fact, just the opposite: At a time many Republicans are distancing themselves from the politically wounded president, McCain is embracing him.

"I feel more comfortable disagreeing with the president when his numbers are up than when they're down," he says. "It's just my nature to not want to pile on."

Still, the detente has paid early dividends for McCain in important battleground states. Ana Navarro, a Republican activist in Miami, says big-time donors loyal to the Bush family are signing up to contribute to McCain. Ronald Weiser, a Michigan real estate developer who was Bush's state finance chairman in 2000, told me he's now backing McCain. Even Sam and Charles Wyly, two Texas businessmen and longtime Bush supporters who funded $2 million in attack ads against McCain in 2000, have given McCain's political action committee $20,000 (the PAC announced recently it was returning the donation because the brothers reportedly are under investigation for possible tax infractions).

"We didn't go to the Wyly brothers; they came to us," says campaign manager Davis. So did many others in the fundraising community. "They see John as a winner, and that's where they want to place their bets."

McCain says he started thinking about running for president again on the day after the November 2004 election. Then Iraq heated up while the domestic centerpiece of Bush's second term, Social Security reform, died in congressional committee. As Bush's poll ratings plunged, the political class and its chroniclers in the media started focusing on the race to come -- and on McCain as the one man who could preserve the White House for Republicans. "All of a sudden we were drinking from a fire hose, and it hasn't stopped," says Davis. "Nobody sat around and wrote out a strategy. It just happened."

McCain has already raised $6 million and donated $1.2 million to Republican candidates, says Davis, twice as much as any other Republican. Staff members know they won't be working on a shoestring in 2008.

"We'll be in good shape," says Weaver. "We'll have a 50-state structure by early next year, as opposed to a three-state structure last time. The house will be ready. Hopefully, we'll have an occupant."

THIS PAST MAY, the potential occupant was in Lynchburg, Va., attempting some major repairs. McCain came here to give the commencement address at Liberty University at the invitation of its founder and president, Falwell, his former antagonist. Dozens of reporters and camera crews made the journey from Washington to record the cessation of hostilities between a leader of the Christian right and one of its most visible critics. Both men smiled for the cameras, and Falwell told everyone who asked that he believed McCain was one of several intriguing prospective presidential candidates whom he could support in 2008. Neither made any reference to the South Carolina primary or McCain's "agents of intolerance" speech.

McCain did four university commencement speeches this past season. At each he gave the same talk, emphasizing civility and pleading for Americans to recognize one another's essential goodwill even as they carry on a spirited debate on divisive gut-wrenching issues such as the war in Iraq. At Liberty, the speech went down easy, garnering polite applause from graduating seniors and their parents. But on a grassy ridge just beyond the campus, a small band of students gathered to protest McCain's appearance.

Being members of the right-wing Young Americans for Freedom, the protesters were neatly dressed and painfully polite. They were also extremely fed up with McCain. On every issue they ticked off -- immigration, campaign finance reform, the gay marriage amendment -- McCain was on the wrong side. "On immigration, he's the symbol of the amnesty movement; he's spoken out consistently against Christians, comparing us to Louis Farrakahn; and he voted against the marriage amendment," said Nathan Rager, 20, a political science major. McCain could talk all day long about civilized discourse and reconciliation; Rager and his friends weren't buying.

Neither are many other movement conservatives. Grover Norquist, head of Americans for Tax Reform and a longtime McCain antagonist, has accused him of flip-flopping on gun control and taxes. Lou Sheldon, founder of the Traditional Values Coalition, has said McCain is not a loyal Republican. Rush Limbaugh has denounced him as a "RINO -- Republican in Name Only."

McCain concedes that some Christian conservatives will never accept him. But there are others who appreciate his antiabortion voting record, his support for Israel, his loyalty to the president and even his support for legislation combating climate change, which has become an important issue for some evangelicals. When I ask him about Falwell, he pulls out a photo the rotund reverend inscribed for him at the Liberty commencement. It reads: "You are a great American, a national treasure and I am glad to say my good friend."

"He may well endorse someone else for president," says McCain. "But he's not my enemy. He's my friend."

McCain emphasizes his solid conservative voting record -- he's antiabortion, anti-gun control, pro-death penalty, and he favors cutting back the size and reach of the federal government, with the vehement exception of the Pentagon. He has switched his stand on ethanol, which he once derided as a boondoggle but now says makes sense, given the fact that gasoline exceeds $3 a gallon. He has voted to extend tax cuts that he once opposed. All of this is either called pandering or bridge-building, depending on your point of view.

"John's challenge, if he chooses to run, is to prove that he wants to be the leader of a party, not just a movement," says Lindsey Graham. "And that means you have to reach out to people who have been adversaries on particular issues."

Or as Jon Stewart put it in when McCain appeared on "The Daily Show" in April: "You're not freaking out on us? . . . Are you going into crazy base world?"

McCain's reply: "I'm afraid so."

However much he courts the base, it will never be enough to allay the suspicions of diehard opponents on the right, who loathe what the National Review's Rich Lowry calls McCain's "richly layered history of apostasy."

On the other side of the ideological divide, Democrats are accusing McCain of moving too far to the right. In a series of recent press releases, the Democratic National Committee has branded McCain's campaign the "Double Talk Express," saying he has flip-flopped on taxes, abortion rights, ethanol and his support for Bush.

"The best-kept secret on the campaign trail is that McCain isn't talking straight to the American public -- he's pandering to the right to get the Republican nomination," says DNC spokeswoman Stacie Paxton. "Once people learn more about John McCain, he is going to lose those crossover votes."

Ask McCain who is the most likely Democratic nominee, and he unhesitantly points to Hillary Clinton. It appears to be his genuine belief but also a highly convenient one. No one scares Republicans as much as Hillary, and no one can make a better case that he can slay the Hillary Dragon than McCain because of his appeal to independents and blue-collar Democrats.

Chuck Yob is one of Michigan's two Republican national committeemen and a card-carrying conservative. He supported Bush in 2000 but has since become close to McCain. His son John, a political consultant, is working for McCain's political action committee. On McCain's recent weekend in Michigan, both the Yobs accompanied him to each stop, offering a running commentary on the state's political makeup.

"Michigan has not gone Republican in a presidential election since George Bush's father beat Michael Dukakis in 1988," says Chuck Yob. "John gives us a real chance to finally reverse that trend. If we want to keep the White House in 2008 against Hillary Clinton, with all her money and name recognition, it's a pretty short list that can beat her."

Sen. Trent Lott, the Mississippi Republican, is a longtime McCain antagonist who has become a close supporter. He predicts that McCain's problems with conservatives will fade as he makes the rounds, presses flesh and shows he's listening to them. "I don't think John necessarily has to make the transition from maverick," says Lott. "That's part of his persona and of his attraction, even to Republicans. He's willing to take on big issues, and he's dogged. You may not agree with him, but you have to admire him.

"Here's the other side: What choice do they have? Where are they going? Do they want to win, or do they want purity?"

IT'S SUNDAY NIGHT, and McCain is presiding over a small corner table at Joe's Stone Crab in Miami Beach. He's sipping a vodka on the rocks with an onion, and he's ordered some of his favorite food, stone crabs, with one of his favorite colleagues, Lindsey Graham ("my illegitimate son," he quips), and gossiping about his favorite subject: politics. They're speculating about the prospects of the Republicans losing the House or the Senate or both, and conjuring up scenarios that might help turn things around.

What about if Rumsfeld resigns in October? Graham asks.

McCain just smiles. Secretary of Defense Donald Rumsfeld is the administration official whom McCain holds most responsible for mistakes in the execution of the Iraq war plan and aftermath, but McCain has stopped criticizing him in public. "If I attack him, it hurts the president," he says.

When you break it down to individual races, McCain says, he believes most Republicans will survive. But he bemoans the predicament of his close friend Joe Lieberman, the Connecticut Democrat, who is under attack within his own party because of his support for the Iraq war and will eventually lose a hotly contested primary to wealthy antiwar challenger Ned Lamont. He sees Lieberman's distress as another example of hardliners imposing ideological litmus tests on moderate politicians.

After dinner the waiter says the man at the next table has insisted on picking up the tab. McCain politely declines. He goes over and explains to the man that campaign finance rules don't allow it.

More than any other Republican senator, McCain has presented himself as leader of a crusade to clean up Washington by imposing tougher rules on donations and lobbying. In 2002, after a seven-year struggle, he and Wisconsin Democrat Russ Feingold rammed through a campaign finance reform law banning "soft money," unlimited campaign contributions to political parties from corporations, trade unions and law firms. The measure has probably done McCain the most damage with Republican-dominated interest groups such as the National Rifle Association and the antiabortion movement, which contend it has hurt their fundraising operations and infringed on their right of free speech. And it brings out McCain's combative streak.

Bradley Smith was chairman of the Federal Election Commission when the McCain-Feingold bill became law. Smith was put on the FEC at the behest of Sen. Mitch McConnell (R-Ky.), an opponent of the bill, and he infuriated McCain, who believed Smith and his fellow commissioners were undermining the new law by dragging their feet on implementation.

Smith recalls attending a committee hearing where McCain was present. "I thought, Well, here he is. I'll go shake his hand, break the ice, show him I don't have horns. I'd just had abdominal surgery a few days before, and I was in a wheelchair." Smith says he rolled up to McCain and held out his hand. McCain took it instinctively before he realized whose it was. "He said, 'I'm not going to talk to you, you're a bully and a coward,' and, frankly, he did not let me say anything.

"Here's a guy who goes around giving commencement speeches saying we should treat each other with civility and respect, but that's not how he treated me," Smith says. "In my view, he doesn't always walk the walk."

McCain says he was reacting to Smith's harsh treatment of two reform proponents at a previous FEC hearing. "He had bullied both of them in a very, very inappropriate fashion. I didn't yell at him, I didn't curse at him. I just said, 'I don't want to shake hands with you'. It's my privilege."

McCain's temper surfaced again a few weeks ago when he scolded Sen. Barack Obama of Illinois, one of the Democratic Party's bright new stars, for purportedly reneging on his commitment to a compromise on lobbying reform. "I would like to apologize to you for assuming that your private assurances to me . . . were sincere," McCain wrote Obama in a stinging letter released by McCain's office. "Sorry for the confusion, but please be assured I won't make the same mistake again."

Immigration reform is McCain's latest crusade and trickiest balancing act. He and Sen. Edward Kennedy of Massachusetts have pushed through the Senate a compromise that allows for stricter enforcement of the law against illegal immigration but also offers a mechanism under which illegals can turn themselves in and qualify eventually for citizenship.

Without McCain's tenacity, Kennedy says, the deal wouldn't have happened. "Where you really saw John's leadership was in the meetings we had early each morning with four or five Democrats and five Republicans," Kennedy recalls. "He stayed focused, and he was well-informed. Even the Democrats listened carefully to him."

For the first half of his Senate career, McCain was considered a showboat by many of his colleagues. But Kennedy and admirers in both parties say that McCain's stature has grown and that he has emerged in recent years as one of the chief architects of bipartisan compromise. "John really is a throwback to a time when senators believed in the institution and made it work," Kennedy says. "He wants to get things done."

But some Republicans remain enraged by the immigration bill. House Republicans passed their own version of immigration reform, one that focused strictly on enforcement, creating tougher penalties against illegals, with no prospect for citizenship. On the hustings McCain has faced small but vocal protests in Arizona, Florida and South Carolina and skepticism elsewhere. He says people often put aside their anger after they listen for a while, and aides cite polls indicating that more than 70 percent of Americans favor the Senate bill (ignoring other polls that suggest the opposite). But he concedes that an important segment of the Republican base is furiously opposed.

McCain and some of his fellow Republican senators are locked in negotiations with House members to see if they can forge a compromise. While the talks are on, McCain is trying to stay on his best behavior and resist the urge to condemn opponents. He warns that voters will punish the GOP for inaction on perhaps the most important domestic issue facing Americans.

Still, there are times when his passion boils over. "I get a little emotional when I see this nativist -- and that's the kindest word that I can use -- backlash" against illegal immigrants, he told a group of Republican activists and potential campaign donors in Miami one night in July. "Yes, they came here illegally; yes, they broke our laws; yes, they have to pay a penalty for doing that. But the thought of rounding up 11 million people and sending them back to the country they came from . . . is an insult to your intelligence and, frankly, a direct contradiction of what America's all about."

He was just warming up. "I have bitten my tongue until it's bleeding and said: Look, we want to reach out; we want to talk to our friends on the right; we need to have a dialogue; we all agree that the problem has got to be solved." But, he added, "I'm not interested in calling some soldier in Iraq and telling him that I'm deporting his parents. Under this House bill, if a young woman is illegally in the United States of America, and she is raped, and she goes to a rape counseling center, the people running the center are guilty of a felony. Is that what America is supposed to be about?

"I don't think so."

AT A HEARING THIS MONTH, McCain and other members of the Senate Armed Services Committee listen as two top military commanders describe the deteriorating security situation in Baghdad. "The sectarian violence is probably as bad as I've seen it," says Gen. John P. Abizaid, commander of U.S. military operations in the Middle East.

McCain questions the U.S. strategy of shifting troops from one Iraqi hot spot to another without ever defeating the insurgency. "What I worry about is we're playing a game of whack-a-mole here," he says. "It's very disturbing."

From the beginning, McCain has been an ardent supporter of the war but a vocal critic of the way the Bush administration has conducted it. In hearing after hearing, he has singled out Rumsfeld and some members of the joint chiefs of staff for not sending in enough troops, disbanding the Iraqi army and failing to anticipate the insurgency that arose in the aftermath of the 2003 invasion.

"I saw we were making serious mistakes in Iraq and tried with everything in me to get a policy change," he tells me. "We paid a heavy price for those mistakes. But saying that, I still believe the consequences of failure now would be disastrous."

In some ways, he has positioned himself to the right of the administration on the war. In a landmark speech last November at the American Enterprise Institute, McCain called for a counterinsurgency strategy of creating "safe havens" that would require more American troops, more spending, more years of occupation and more casualties. "We must get Iraq right," he insisted at the time.

McCain says now he recognizes that with domestic public opinion so opposed to the war, it isn't possible politically to send in more troops. "I don't think he could sell that," he says of Bush.

While the war threatens to do huge political damage to Republicans, McCain's backers are counting on his credibility as a military veteran and defense expert to see him through. Even some of the war's most vocal critics have confidence in his savvy and feel. "John never would have taken us into Iraq the way Bush did, without listening to the commanders on the ground," says Bob Kerrey, former Democratic senator from Nebraska, who like McCain is a Vietnam veteran.

Having survived a plane crash and a North Vietnamese prison camp, McCain thinks of himself as a man of a certain destiny. "There's no doubt about it. Not that I'm a chosen person or anything like that. I just think that I'm the luckiest guy I know. I mean when I'm on a plane with Cindy and the weather gets bad, I say, don't worry, I'm dying in bed. If I was gonna die in an airplane, it would have happened long ago."

Officially, McCain hasn't decided whether to run. He says he'll sit down with Cindy and the children at Christmastime and discuss it. Unofficially, he's ready. Still he says, he's told his staff: "Look, if we run it's got to be enjoyable. I'm not gonna spend time being unhappy and tense and 'Oh, God' all the time."

Besides, he adds, speaking of his purported friends in the media, "If I tried to do anything differently, they'd kill me."

There's one more stop on the Michigan run: the town of Iron Mountain, population 8,154, in the Upper Peninsula. As McCain's plane pulls up on the small airstrip, Chuck Yob is briefing him. Upper Peninsula folks call themselves "Yoopers," as in U.P., and they're proud, rugged and individualistic. The area is predominately Catholic, antiabortion and anti-gun control, but voters have tended to go Democratic in recent years because of pocketbook issues. McCain, Yob believes, can turn that around. They don't get many celebrities up here, Yob says, and McCain should pull in a good crowd.

Sure enough. More than 200 people are waiting as we pull up at the Chippewa Club, a Victorian-era house that used to be the home of a mining executive back in the days when the industry thrived here. They start whooping and hollering as McCain emerges, and they don't let up for a good five minutes. Some are carrying hand-lettered signs with "McCain 2008!" and some are chanting his name. He's moved and excited.

He tells them he's grateful for their attendance, that he knows they could be home having dinner with their families. "This is really what America is all about, and it's a great honor to be with you tonight. This is really the fun part of politics for me."

It shows. As a purple dusk descends behind his head, he launches a stump speech with a bit more edge when he gets to Iraq. "Look, we should acknowledge the fact that we made some serious mistakes in Iraq and Rumsfeld was responsible for them -- I'll give you a little straight talk -- because we didn't have enough troops there. And the military guys knew it, and I knew it. But we still have to win, and we still have to prevail."

After the speech, the crowd mobs him for handshakes and photographs. A Vietnam vet in biker's gear and a braid in his hair is sobbing. A World War II veteran rises out of a wheelchair to shake McCain's hand. They give him presents: an Upper Peninsula flag, a hunting knife and a pair of antlers from a white-tailed deer.

"America" is playing on the loudspeaker. McCain's handlers try to clear a path to the car, but neither the candidate nor the crowd is ready to let go. It takes 20 minutes for Weaver and Yob to drag him from the scene.

Yob likes what he sees. "This guy can do what Ronald Reagan did for us. I'm just waiting for the starting gate to open."

McCain also relishes the moment. "That was really an amazing thing," he says later, as the plane takes off for another campaign stop, another hotel room, another fundraiser. "Did you see that old guy in his wheelchair? Oh, God, it was wonderful."

Glenn Frankel is a staff writer for the Magazine. He will be fielding questions and comments about this article Monday at noon at