MERRIMACK, N.H. — It ain't over.
Women poured into Democratic primary polling places in New Hampshire with a loud message for the rest of the country: We're for Hillary.
They delivered a dramatic, come-from-behind victory for Sen. Hillary Clinton over Sen. Barack Obama that checked what many thought was his march to the nomination and the history books.
Clinton's dramatic comeback set up what could be an epic struggle in coming weeks, a clash between generations and political styles underscored by the historic possibility of nominating an African-American or a woman for the first time.
Republicans also resurrected an endangered candidate and now face a coast-to-coast struggle as well.
The New Hampshire Republican primary went to John McCain, a maverick who promises to win the war in Iraq and overhaul the way Washington works.
Just five days earlier, Iowa went for another outsider promising change, Mike Huckabee.
The two must face one another and several other rivals in weeks to come, in a wide-open race. First comes Michigan next Tuesday, where McCain, Romney and Huckabee will square off. Meanwhile, former Tennessee Sen. Fred Thompson already left New Hampshire for South Carolina, working for a victory there on Jan. 19. Former New York Mayor Rudy Giuliani is headed to Florida, looking for a Jan. 29 win there.
The picture is clearer in the Democratic Party, where it appears to be a two-person race and a contest over who has the more appealing voice and the style better suited to deliver such Democratic goals as ending the war in Iraq and expanding health care.
Obama had momentum from Iowa, his fresh face and upbeat message appealing to young people. Overnight he had become the very face of change at a moment in history when Americans hunger for it in many ways. Many pre-election polls hinted that Obama might win in a landslide.
But Clinton still has the most famous brand name in the party. She fought back in New Hampshire, retooling her message to take on Obama directly as a waffling newcomer. Former President Bill Clinton jumped in as well, calling Obama's pitch a "fairy tale."
By stressing her experience in the White House, she convinced many that she knew how to pull the levers of power.
While both Obama and Hillary Clinton personify historic change — the first African-American and woman with real chances of being nominated and elected — Clinton and Obama offer vastly different approaches.
He's the freshest face in a party that historically embraces newcomers. In the last half-century, Democrats only twice nominated non-incumbents who'd run nationally before — Hubert Humphrey in 1968 and Al Gore in 2000.
Obama looks more like change. A new face, a new generation — and a promise of a new, more civil approach to politics that resonates particularly with the post-Baby Boom generation that came of age after the combative '60s.
But Clinton, who was on the verge of being written off by some pundits, showed a resilience that should allow her to tap into her well of organized supporters and donors, particularly among women of her own generation.
The Clinton-Obama contest will be fought along generational and gender lines that divide the party and help explain Tuesday's results.
Women represented a lopsided 57 percent of the vote, exit polls showed; they went for Clinton by a margin of 47-34 percent, while men went for Obama by 42-30 percent.
Voters under the age of 30 went for Obama by 61-22 percent, while those aged 65 and older went for Clinton by 48-33 percent.
The key question going forward to contests in Nevada on Jan. 19, South Carolina on Jan. 26, then a rush of more than 20 states on Feb. 5, is how much the two candidates will adapt.
Obama, for example, will face intensified scrutiny. With Clinton in close pursuit, he also might have to sharpen his message or risk looking too cautious, a mistake Clinton herself made last fall when she thought she had a solid lead.
She has to decide how hard to hit Obama in the weeks to come, and whether that would weaken him as it did in New Hampshire — or spur a backlash against herself.
For Republicans, the contest turns next to Michigan, which votes next Tuesday. McCain won there in 2000, but Romney has strong ties in the state, which his father served as governor.
Republicans then face off in what could be a hotly contested primary in South Carolina. McCain lost there in 2000, Thompson hopes to make a regional pitch and Huckabee looks to get on the comeback trail in a state with more Christian conservatives.