After a surprise, narrow victory in New Hampshire, Sen. Hillary Clinton went home to New York Wednesday to "get grounded and take a deep breath."
Sen. Barack Obama, stung by his second-place finish in New Hampshire after his overwhelming win in Iowa, suggested his campaign would begin employing Chicago-style smackdown in his battle with Clinton for Democratic voters.
"I think that Sen. Clinton, obviously, is a formidable and tough candidate, and we have to make sure that we take it to them just like they take it to us," Obama said Wednesday.
"I come from Chicago politics. We're accustomed to rough and tumble."
Obama went after former President Bill Clinton Wednesday, accusing him of "mischaracterizing" his position on the Iraq War.
"Former President Clinton has continued to mischaracterize my record on this, and we're going to have to call him on it," Obama said on NPR's Morning Edition. "The press has already pointed out that he's wrong about this, but he keeps on repeating it."
Obama was referring to comments Bill Clinton made on the eve of the New Hampshire primary: "It is wrong that Sen. Obama got to go through 15 debates trumpeting his superior judgment and how he had been against the war in every year, enumerating the years, and never got asked one time -- not once, 'Well, how could you say that when you said in 2004 you didn't know how you would have voted on the resolution?'" Clinton said at a campaign rally at Dartmouth College in New Hampshire Monday night.
"Give me a break. This whole thing is the biggest fairy tale I've ever seen," the former president said.
"The real fairy tale is, I think, Bill Clinton suggesting somehow that we've been just taking a cakewalk here," The Associated Press reported Obama saying.
On National Public Radio Wednesday morning, Obama lashed out at Bill Clinton. "At some point we are just going to keep drilling away at the fact that it is indisputable," he said.
"I opposed this war from the start. In 2002, 2003, 2004, and the fact that I voted for funding for the war once I got into the Senate is perfectly consistent with my position that it was important to make sure that our troops had the equipment and the tools that they needed at a time when things were very dicey."
Obama received the backing Wednesday of the 60,000-member Culinary Workers Union local in Nevada and the endorsement of the state's chapter of the Service Employees International Union.
Fresh from its win in the Granite State, the Clinton campaign evaluated election strategy going into upcoming primaries in Nevada, Michigan and South Carolina, as well as the Super Tuesday primary Feb.5 in which two dozen states go to the polls.
"I'm going to keep going as we take on all the rest of the contests between now and February 5," Clinton said Wednesday, according to the AP.
After Tuesday night's slim victory, Clinton credited her connection with women and "fiercely independent" New Hampshire voters, who gave her a narrow victory in a state known to surprise on election night.
The New Hampshire voters held true to their reputation as contrarians, bucking the polls that pegged Obama the winner and casting ballots Tuesday in what Clinton characterized as "a really representative election."
Clinton beat out Obama, who rode a wave of momentum from the Iowa caucus into the Granite State, winning narrowly by only a few percentage points there.
Clinton's historic victory in New Hampshire makes her the first woman, and first former first lady, to win the Granite State primary.
This morning, Clinton told "Good Morning America's" Robin Roberts she had a good feeling about her chances yesterday and didn't pay attention to the polls.
"The voters of New Hampshire are fiercely independent, and they give you the once over," Clinton told Roberts.
Never thought to be a major factor in New Hampshire, former North Carolina Sen. John Edwards came in a distant third in the state, garnering 17 percent of the vote, and will now focus his limited resources on South Carolina, where he won in 2004.
In her victory speech Tuesday night, Clinton told a crowd of supporters in Manchester, "Over the last week, I have listened to you, and in the process I found my own voice."
This morning, Clinton said her much-talked-about emotional moment Monday speaking to a group of mostly women voters may have given her credibility with older women, who turned out in high numbers for her. "I think it could well have been," she said.
Clinton had been responding to a voter who asked her how she does it.
"I've asked that question to people in so many settings for so many years," Clinton told Roberts, "and we're finally understanding what that's about."
"I've always considered myself a servant-leader," Clinton said. "I felt that I could finally convey that to people, and I felt that I could connect that in a profoundly personal way."
However, the woman who sparked the emotional response from Clinton admitted Wednesday that she voted for Obama.
"I went to see Hillary. I was undecided, and I was moved by her response to me," Marianne Pernold Young, 64, a freelance photographer from Portsmouth, told ABC News in a telephone interview.
"We saw 10 seconds of Hillary, the caring woman," she said. "But then when she turned away from me, I noticed that she stiffened up and took on that political posture again," she said. "And the woman that I noticed for 10 seconds was gone."
With his numbers among young voters and women in New Hampshire not what they were in Iowa, Obama said this morning on "GMA" that his campaign was "working it hard" in what he deemed "a close contest."
Obama tried to speculate on what led to his second-place finish in the Granite State.
"College students aren't back in school," the Illinois senator offered. "Sen. Clinton ran well among women in New Hampshire."
And what about former President Clinton's Monday comments that Obama's candidacy was a "big fairy tale?"
"President Clinton is passionate about his wife and wants to see her win," Obama said. "And during the course of this week said some things that distorted my record."
In his post-primary interview with Robin Roberts, Obama shifted focus to the larger race, saying that "voters are excited about the Democratic field. We're attracting a lot of independents and a lot of Republicans to vote Democratic this year." Obama said that people who thought they knew what voters were thinking was "fooling" themselves.
After a devastating third-place finish in Iowa, the narrow victory in New Hampshire allows Clinton to claim a comeback of sorts, a narrative that fits well with her husband's surprise 1992 finish in New Hampshire that led to his nickname "The Comeback Kid."
The tight race has also secured Obama as a formidable opponent for Clinton, setting up what may become a bloody political battle between the two Democratic rivals going into the big-state primaries Feb. 5.
"I come tonight with a full heart," Clinton told a crowd of supporters in Manchester. "Together let's give America the kind of comeback that New Hampshire has just given me." Supporters chanted "Comeback kid!"
"We're going to take what we learned here in New Hampshire and make our case," she said. "We are in it for the long run!"
Over 24 hours, the Clinton campaign went from despair and bitterness to euphoria, buoyed by the victory in New Hampshire.
"We're back," Clinton pollster Mark Penn told ABC News.
Looking tired and disappointed, Obama conceded victory to Clinton, speaking to a crowd of supporters who were yelling "We want change!"
"You can be the new majority who can lead this nation out of a long political darkness -- Democrats, independents and Republicans who are tired of the division and distraction that has clouded Washington," Obama said.
"If we mobilize our voices to challenge the money and influence that's stood in our way and challenge ourselves to reach for something better, there's no problem we can't solve, no destiny we cannot fulfill," he said.
Both Obama and Edwards called Clinton Tuesday night to congratulate her.
Introducing her husband at a rally in Manchester, Elizabeth Edwards said, "The goal is still in sight."
Conceding defeat in the Granite State, Edwards congratulated both Obama and Clinton but vowed to continue his campaign.
"Two races down, 48 states left to go," Edwards said before a crowd of supporters.
Long before the final count came in for the Democratic primary in New Hampshire, New Mexico Gov. Bill Richardson took to the stage at his rally in Manchester admitting defeat for a second time but refusing to bring his campaign to an end.
"We head out west and the fight goes on," Richardson told the cheering crowd of about 150 supporters.
Hours before her victory in New Hampshire, Clinton made a major shakeup in the top echelons of her campaign.
Maggie Williams, Clinton's former chief of staff from her days as first lady, was tapped to take the reins of the campaign and will be in charge of day-to-day operations.
"Maggie brings a comfort level," a Clinton campaign source told ABC News' Kate Snow. "She is a woman. She's a minority. She can talk the talk, and she understands the field operations."
Exit poll results suggested Clinton's candidacy resonated with women, especially older women.
Clinton's campaign inspired a gender gap in New Hampshire, with Clinton winning by 9 points among women voters, while Obama won men by a wide 42 percent to 30 percent margin.
Among women ages 65 and over, Clinton won 57 percent to Obama's 27 percent. In comparison, Clinton and Obama tied at 39 percent among men 65 and over.
The economy was the single biggest issue to voters, and that worked for Clinton as well. Among those who called it their top concern, she beat Obama by 9 points, 44 percent to 35 percent.
Obama won the message game. Exit poll results indicate 55 percent of Democratic primary voters said they're most interested in a candidate who can bring about needed change.
Only about two in 10 say they care most about experience -- the message most touted during the campaign by Clinton.
In recent days, the New York senator had begun to retool her appeal to voters, lessening her emphasis on experience and raising questions about Obama's ability to bring about the change he promises.
Clinton won mainline Democrats, by 45 percent to 34 percent; Obama won independents by a wider 45 percent to 30 percent. Independents accounted for just over four in 10 New Hampshire voters, down from 48 percent in the last primary in 2004, and a high of 50 percent in 1992.
All of the Democratic candidates poured resources into the Granite State.
But in the end, it was Clinton who beat out her Democratic rivals, securing her position as a leading Democratic presidential candidate, and giving her campaign renewed energy in its battle with Obama for Democratic voters.
ABC News' John Donvan, Kate Snow, Sarah Amos, Raelyn Johnson, Sunlen Miller, Gary Langer and The Associated Press contributed to this report.