John McCain's campaign bus is about as close to a rolling locker room as you'll find in politics. There's a lot of hanging around and ribbing. McCain is the top jock--everyone knows he's the toughest guy aboard, having endured an inferno, a couple of plane crashes and years of sadistic torture.

The Arizona senator pokes fun at himself, and at his "incompetent staff, most of whom are on work-release programs from prison." He even pokes fun at his heiress wife: "Sure, Cindy makes her own clothes," he says, rolling his eyes. "Those girls who attend the University of Spoiled Children" (also known as the University of Southern California) "are trained at the Theta house to make their own clothes."

Is this why men like him so much?

One of the most striking things about McCain's race for the Republican nomination against Texas Gov. George W. Bush is the gaping gender gap between the two in New Hampshire. A Washington Post poll last month found that McCain led Bush by 14 percentage points among men, while Bush led McCain by 17 points among women.

A similar chasm divides the candidates in the other primary, the Post survey and more recent polls in the state have found. Bill Bradley leads Al Gore among men by some 15 percent, while Gore is even or slightly ahead among women.

Bradley has his own macho credentials, of course, having traded elbows with the likes of Bill Russell on his way to the National Basketball Association Hall of Fame. When the former New Jersey senator campaigns, his path is clogged with men who know him for his Olympic gold medal, his college scoring records, his days on the champion New York Knicks.

"I saw you play basketball when I was at Cornell! You killed us two straight years," a Dartmouth professor named Stan Rosenberg said in greeting Bradley one morning in Hanover. There are eruptions like this every day. New Hampshire is crawling with fans of the nearby Boston Celtics, and while they would no doubt prefer to elect John Havlicek president, they seem willing to settle for Hondo's worthy rival. Sometimes gender stereotypes are true: Boys grow up pretending to fly fighter jets and dreaming of sinking the winning shot as the buzzer sounds. Is it any wonder that thousands of men are drawn to McCain the brave pilot and Bradley the hero jock?

But there is more to it, say experts in gender-gap politics. Substance and strategy also separate the candidates. And the fact is, appealing to men is passe. The last major figure to lead among men yet trail badly among women was Robert J. Dole in 1996.

Pollsters from both parties give Bush high marks for targeting, and so far winning, female supporters.

"Of the four front-runners, George Bush understands best how to target women," says Celinda Lake, a Democrat. "The whole idea of 'compassionate conservatism' appeals to women. His first advertisements highlighted education. He does photo-ops with diverse audiences, and appears frequently with his wife. He's been very savvy about it."

Most Republican strategists believe their party has an image problem. Focus groups turn up such words as "mean," "heartless" and "scary." A big reason Bush is popular with the GOP establishment is that he strikes women and minorities as friendly compared with Republican leaders in Congress.

"The first way that McCain became known in this race was for his strong support of action in Kosovo," says Republican pollster Linda DiVall. Women, she asserts, tend to be less hawkish. "So while women may not know a lot about George W., what they know is positive," DiVall said. "He talks about inclusion and compassion and how his tax cut would affect a single mother with two kids."

The Bradley-Gore dynamic is less clear-cut for the experts. There is the hero worship, and the related name recognition. Bradley played basketball long before Michael Jordan. Jocks weren't omnipresent. Far more men have heard of him than women.

Strong support from women reelected President Clinton in 1996, and women--especially African American and elderly women--remain his most stalwart fans. That trickles down to his vice president. And Irene Natividad of Womenvote 2000 believes that women are more drawn to specifics than to Bradley's vast picture. "Big vision is great," she says, "but what women want to know is the everyday fix-it solutions. . . . What are you going to do for me today on things I care about--health care, children, and, as I age, economic security?"

All of this is mainly a matter for New Hampshire; in national polls, Bush and Gore are ahead with women and men alike. Bradley is convinced that the more women get to know him and his liberal agenda for education and health care, the more they will like him. When he rejects Gore's repeated offers to scrap television ads in favor of more debates, Bradley always cites his need to become better known. The subtext here is better known by women.

He's looking for more Jean Faheys. The public school teacher from Claremont says of Bradley: "He espouses a lot of the social ideals I hold as a Democrat, and I believe he speaks from the heart."

Still, when The Post gathered a group of New Hampshire Democrats to watch a recent debate, all the men went for Bradley, and every woman except one backed Gore.

McCain, meanwhile, has fielded questions on a women's Internet site and has made his defense of Social Security and Medicare almost as prominent as campaign finance reform in his speeches.

At a town meeting with McCain in Bow last week, the room was packed, but at least six out of 10 citizens were men. When questions came, most were from men--many of them veterans, who typically began by hailing McCain's heroism.

Barbara Trulson was there, and afterward she said she is torn. She likes the advisers Bush has chosen, and she likes McCain's independence and openness. Trulson thinks men go for McCain and Bradley because "men catch on to people who aren't candid," while "women are susceptible to charm."

"Just look at who we have in the White House now," she added. She may go for McCain. But she has to warn him: "I don't vote like the average woman."

CAPTION: Bow, N.H., residents--a majority of them men--listen to GOP presidential candidate John McCain, who is favored by men in state Republican polls.

CAPTION: Sen. John McCain, left, with former senator Warren B. Rudman (R-N.H.) talks with resident in Amherst, N.H.