When Vice President Biden arrives in South Carolina on Friday to headline a sold-out dinner for state Democrats, here’s what you can expect to go down:

Biden will stoke speculation that he wants to run for president in 2016 by pressing the flesh in the first-in-the-South primary state. He will show himself to be on a first-name basis with many of the local politicians and county activists who will line up to greet him. They will gush over his attributes — genuine, down-to-earth, rock solid on the issues. As Dick Harpootlian, the state party chairman, put it, “We’re tickled pink to have him.”

Yet by the time he leaves, the reality of being Joe Biden will sink in: A promotion to the top job is a long shot, at best.

For Biden, who, his family and advisers say, is weighing whether to run in 2016, several paradoxes are at work. He is beloved by grass-roots Democrats, but mainly as the avuncular No. 2 to Barack Obama. From the South Carolina Lowcountry to the Iowa heartland, there are no signs — none yet, at least — of a “Draft Joe” movement. “There just isn’t,” said Sue Dvorsky, a former head of the Iowa Democratic Party.

Biden clearly has the experience and gravitas to ascend to the presidency, but many Democrats say he may have been in Washington too long (since 1973) to win an election. He is President Obama’s governing partner yet is rarely seen as Obama’s heir apparent. For that mantle, and for the nomination, he is likely to face stiff competition in the form of Hillary Rodham Clinton, the former secretary of state and, according to most everyone, the 2016 front-runner.

Washington Post photojournalist Melina Mara talks about her behind-the-scenes photos of Vice President Joe Biden. Mara received unprecedented access to the vice president as he rode in his limousine and met privately with advocates, politicians and civil rights leaders. (Jason Aldag/The Washington Post)

“Because she’s a Democrat, I can’t say she’s the elephant in the room, but she’s certainly the dominant donkey,” said Robert Shrum, a veteran Democratic presidential campaign strategist. “If she decides to run, it’ll be almost impossible to prevent her from being the nominee. If she doesn’t run, I think Biden’s the odds-on favorite.”

Yet even then, “he will not have it easy,” said Donald Fowler, a former Democratic National Committee chairman and South Carolina native who is close to the Clintons.

Biden remains a distant presence in the 2016 field. One Democratic politician who is considering a presidential run has focused his deliberations with advisers entirely on how, or even whether, to challenge Clinton. According to one of the advisers, Biden has not entered into the equation.

‘Five-dimensional chess’

At some point, Biden will be making some calculations of his own.

“It’s like five-dimensional chess,” said Ted Kaufman, a longtime confidant of Biden’s who was appointed to succeed Biden in the Senate after he was elected vice president in 2008. “You can sit around and think about it and dream about it, but really, it’ll get decided later, and that’s when it’ll get serious.”

People close to Biden laid out several considerations on his mind, starting with fundamental political concerns: Would the country effectively turn backward by picking a baby-boomer white man to succeed a youthful black president? Will the Obama administration three years from now be considered a success, particularly on the economy?

And there’s the matter of whether Clinton runs. This, Kaufman said, is a “major consideration” because “he and Hillary are actually friends.”

The best scenario for a Biden candidacy would be if Clinton stays out of the race, the economy is going gangbusters and voters want a third Obama term. But Biden cannot control these determinants. So, confidants said, he is thinking about more personal factors, including his decades-long presidential aspirations.

Biden, a spry 70, keeps a travel schedule that would exhaust most men half his age. But he will be 73 when the next election rolls around, and those close to him said he knows his age would be an issue.

For Biden, who has been running for office since his 20s, not running would feel unnatural — especially if his vice presidency is deemed successful, those close to him say.

But not running also offers him a chance to make serious money for the first time in his life. Biden, who ranked among the poorest senators, could rake in millions of dollars in short order by hitting the speaking circuit, publishing a memoir or serving on corporate boards. Biden finds the prospect of building a financial cushion for his family particularly alluring, confidants said.

Sometime in the next two years, advisers said, Biden will sit down with his wife, Jill, three children and the rest of their family to decide whether to launch another national campaign. (Biden declined through an aide to be interviewed for this article.)

“I don’t think it’s any real secret that it’s something that he’s going to think about,” said Biden’s eldest son, Beau, the attorney general of Delaware. “I want him to give it real thought. I think he’d make a great president.”

The vice president thinks the 2016 speculation keeps him relevant and helps give the Obama administration political leverage in the second term, people close to him said. If Biden announced that he was not going to run, the thinking goes, it could hasten the administration’s eventual lame-duck status.

Besides, many said, Biden enjoys all the buzz.

“It’s like being a baseball player and people speculating about whether you’re going to be in the Hall of Fame,” Kaufman said. “Clearly, this is the ultimate compliment.”

‘He is himself’

One question hanging over the deliberations is whether Biden can win. He’s run for president twice and failed miserably. In 1988 he withdrew before the primaries after a plagiarism scandal, and in 2008 he dropped out the night of the Iowa caucuses after garnering just 1 percent of the vote.

The odds for a third try are not good, at least based on recent polling — which, 31 / 2 years out, should be taken with a grain of salt. A Quinnipiac University poll released Thursday found that 65 percent of Democrats and Democratic-leaning independents support Clinton, while 13 percent back Biden. New York Gov. Andrew M. Cuomo stood third, at 4 percent.

If Clinton does not run, 45 percent would support Biden, with 15 percent for Cuomo and other potential candidates in single digits.

Relative to 2008, when Obama began as an underdog but overtook Clinton as the front-runner, it could be more difficult for Biden to make a powerful impression and surpass her because his public image is well established.

There’s also the question of whether Biden — a garrulous creature of conventional constituency politics — would appeal to a changed Democratic coalition. Over the decades, Biden built deep ties to working-class whites, who once made up the core of the Democratic base. But in the 2008 and 2012 campaigns, Obama reshaped the coalition to include many more young voters, Latinos, African Americans and gays.

Fowler said Biden would find it harder to adapt to meet the politics of the moment compared with younger possible candidates, such as Maryland Gov. Martin O’Malley or Massachusetts Gov. Deval L. Patrick.

“Joe Biden has just been around too long to do that again,” Fowler said. “He is himself. And the association with Obama is not going to replace who he is.”

In his first five years as vice president, Biden has carved out an identity with core convictions that appeal to the Democratic base — on gun control, on gay marriage, on women’s rights. He doesn’t shy from speaking his mind; last year, he irked Obama’s advisers by publicly coming out ahead of the president in support of legalizing gay marriage.

Privately, Obama’s White House advisers often knock Biden as an unscripted politician drawn to the spotlight and prone to making gaffes. But what they see as a lack of discipline and polish, voters may admire as refreshing candor, supporters say.

“He’s genuinely witty; he’s spontaneous,” Shrum said. “I think it makes him much more real to voters.”

Biden is embracing his caricature. His office recently began a series of podcasts on the White House Web site called “Being Biden” that feature the vice president narrating a behind-the-scenes photograph to give fans a taste of his life. Early installments show Biden at his alma mater cheering on the University of Delaware’s Lady Blue Hens in their locker room during the NCAA playoffs; serving dinner rolls at a hunting club’s wild-game dinner; and showing off his West Wing desk to actress Julia Louis-Dreyfus, who plays a vice president in the HBO comedy series “Veep.”

‘It wasn’t a good deal’

These outtakes belie the seriousness of his role. Some historians have begun calling Biden the most powerful vice president of modern times. Obama tasked him with some of the top priorities of this administration — the 2009 economic stimulus and middle-class recovery, the war in Iraq, fiscal negotiations with Congress, and the push for stricter gun laws.

Biden established a reputation as the administration’s closer, the guy who can cut a deal with a bitterly divided and often paralyzed Congress.

Late last year, it was Biden who negotiated an accord with Senate Minority Leader Mitch McConnell (R-Ky.) to avoid the fiscal cliff. When reporters asked what his selling point was, a smiling Biden said, “Me.” Obama showered praise on the vice president, calling his work in brokering the compromise “extraordinary.”

But Biden’s decision to insert himself in those negotiations was not entirely welcome in all quarters of the White House. Some officials thought he bargained away too much of the leverage they had with the end of the George W. Bush-era tax cuts and got too little in return. The deal did nothing to prevent the automatic spending cuts known as the sequester or to avert another crisis over the debt ceiling.

“It wasn’t a good deal,” one top White House official said at the time. The official, who spoke on the condition of anonymity to discuss internal thinking, also said that Republicans tend to pick up the phone and call Biden when they are trying to get something past the White House that is “not good for us.”

This year, Biden has focused almost exclusively on gun control. Obama tasked him with building public momentum around such proposals as universal background checks for gun buyers and limits on assault weapons and high-capacity ammunition magazines, as well as with lobbying senators to pass them.

Biden succeeded at galvanizing the public but not at the inside game. Just minutes before a Senate minority blocked a compromise on background checks, Biden was exasperated at having been outmaneuvered by the National Rifle Association.

“I hope to God that there’s 60 people up there who have the courage to stand up,” Biden said, referring to the tally needed in the 100-seat Senate. By then, however, he knew the vote was going to fall short.

Still, the tragic backdrop of the gun debate played to Biden’s humane side. Whenever Biden encountered former congresswoman Gabrielle Giffords, who is recovering from a 2011 shooting in Tucson, the vice president would praise the nurses at her side, who tend to go unrecognized.

“To turn his attention for five solid minutes to a nurse and say, ‘You do God’s work’ . . . they come home from our trips just blown away,” said Pia Carusone, Giffords’s top aide.

Biden got emotional every time he spoke about “those beautiful little babies” shot dead Dec. 14 in Newtown, Conn., where 20 children and six adults were slain in a school massacre. He forged relationships with Newtown families, making long calls to them at night from his residence. Sometimes Biden told them about how he lost his first wife and 1-year-old daughter in a 1972 car accident. But often he would just listen.

“Most of the discussion is him with the phone to his ear and listening to a mom and dad’s grief or how they’re coping,” Beau Biden said. “I just think he helps them get to the next day.”

Scott Clement and Karen Tumulty contributed to this report.

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