Levesque's conversion offers a window into how Clinton has emerged as the front-runner for the Democratic presidential nomination: One of the most demonized politicians in America has begun to win a second look from skeptics. And among women and seniors, such as Levesque, she has built big leads over her rivals.

That underscores one of Clinton's most important assets in the turbulent few months ahead of the balloting set for early January. She has built a political base — reflected in polls — of voters who dominate the Democratic nominating process: seniors, women and blue-collar voters.

That's a troublesome trend for Obama, who has drawn his support mainly from the young and the affluent. He had been considered the candidate most likely to slow the Clinton juggernaut. But her lead in national polls has widened. Nationally, Clinton leads Obama 38% to 22%, according to the latest Pollster.com aggregation of surveys. Former North Carolina Sen. John Edwards is under 14%. The latest campaign reports showed that in the last three months, Clinton for the first time raised more money than Obama.

Still, a Clinton nomination is far from a foregone conclusion. In Iowa, whose voters are first in the nominating process, the race is effectively a toss-up among Clinton, Obama and Edwards. Many presidential front-runners have been thrown off course by an early upset or by failing to meet the expectations that attach to the leader in national polls. And Clinton is still struggling to allay a concern among many Democrats that she is too polarizing to win the general election.

Her rivals say that national surveys reflect little more than Clinton's high name recognition. They suggest that most voters have yet to focus on alternative candidates.

"This campaign is still at its early stage for voters," said David Plouffe, Obama's campaign manager. "The vast majority of voters have not made a decision."

But Mark Penn, Clinton's pollster, says that the long primary contest has given voters unusually extensive exposure to the candidates, and so Clinton's standing is built on more than fame.

"What we are seeing in polls is not a reflection of name recognition," said Penn. "It's a reflection of listening to the candidates."

Yet she also has high negative ratings in some polls. For more than a decade, she has been attacked in a shelfload of books, on countless websites and in repeated direct-mail drives. Her detractors see her as a calculating opportunist with a crisis- ridden past.

Paradoxically, Clinton may be benefiting from that unflattering image as she reintroduces herself.

"If she showed up and doesn't have a horn and tail and speaks clearly and engagingly, people say, 'You know, she's all right,' " said Andrew E. Smith, a pollster at the University of New Hampshire.

Levesque disapproved when Clinton ran for the Senate just as her husband was about to leave the White House. Eventually, however, Levesque became impressed with Clinton's Senate career and with the range of issues Clinton addressed as a presidential candidate.

Levesque also cites a factor that Clinton says she often hears: "I really hoped someday I would live long enough to see a woman as president."

Women, who make up the majority of the Democratic electorate, are a vital part of Clinton's political base. Gallup surveys in August and September found that 51% of women aged 18 to 49 supported Clinton, compared with 29% supporting Obama and 10% Edwards. Among older women, the gap in Clinton's favor was even greater.

Taking nothing for granted, the Clinton campaign has aggressively targeted women. A weekly "HillGram" sent to tens of thousands of potential supporters, for instance, deals with such issues as breast cancer, equal pay for equal work and other topics of interest to female voters. The campaign also holds events at venues tailored to women, including a national hairdressers' convention in Boston and children's play centers around the country.

And Clinton's signature issue — healthcare — is a big draw for many women.

"It's a problem for a lot of people's families," said Melanie Sowa, 40, a South Carolina homemaker who supports Clinton because of her gender as well as her pledge to make healthcare more affordable and accessible.

Clinton's pollster thinks Clinton does well among seniors, another important voting bloc, because they place a premium on experience. "Young people don't tend to value experience because they haven't been through a stock market crash or world wars," Penn said.

Clinton's appeal to seniors is particularly important in Iowa, a state where older people have dominated the caucuses.

Whereas Obama's campaign has drawn strength among upscale, college-educated voters, Clinton has been an early favorite among the less-affluent.

"These are traditional Democratic voters who are mostly interested in lunch-pail issues," said Ruy Teixeira, an election analyst at the Center for American Progress, a liberal public-policy group. One of Clinton's focuses is programs for people with economic difficulties.

However, some analysts say Clinton's dominance among blue-collar voters may not last. Often they are not engaged as early in the electoral process as wealthier voters, so they are more likely to change their minds.

"Their support tends to be more impressionistic," said Democratic pollster Geoffrey D. Garin, who is not affiliated with any presidential candidate. "That's why the thing is not a done deal: Their opinions can still change with new events."

For all of Clinton's apparent strength, there is one big rock looming in her path to the nomination: Iowa.

Even among Clinton's core constituencies, her lead is narrower there than nationally. Whereas a national Gallup Poll found a majority of women favoring Clinton for the nomination, a September Los Angeles Times/Bloomberg survey of Iowans likely to participate in the caucuses placed Clinton's support among women at 37%, with 21% favoring Obama and 18% favoring Edwards.

Iowans will cast the first meaningful votes and will probably set the tone for much that follows. A Des Moines Register poll published Sunday put Clinton in first place with 29% among likely caucus-goers, followed by Edwards with 23% and Obama with 22%. However, those results were within the survey's margin of error, and more than half of those polled said they might change their minds.

"There's nobody who's captured any momentum to break out," said David Nagle, an Iowa Democrat with more than 30 years' campaign experience. "There's still an awful lot of play out there."

The advantages that Clinton enjoys nationally are less significant in Iowa. Name identification is not as important, since all the candidates are well known. Money goes only so far in a state where voters put a premium on personal contact. And Iowa is one place where Bill Clinton never campaigned much, so his wife has had to build her own operation from the ground up.

"When a campaign starts to say, 'Come with us — we're the winner,' watch out below," said Paul Maslin, a strategist for New Mexico Gov. Bill Richardson, a Democratic candidate who placed fourth in the Register's poll, with 8%. "Tell a bunch of Iowans this thing is over, and they may very well rise up and say, 'Oh, no, it's not.' "