MANCHESTER, N.H. — Sen. Hillary Rodham Clinton, Democratic presidential front-runner no longer, accused campaign rival Barack Obama of changing his positions on healthcare and "a number of issues" last night in a debate three days before the New Hampshire primary.

"I have been entirely consistent in my position," countered Obama, adding that he and Clinton have a philosophical disagreement over her proposal to require Americans to purchase health insurance or face a penalty from the government.

Obama won the kickoff Iowa caucuses Thursday, and his remaining rivals — Clinton, former Sen. John Edwards and New Mexico Gov. Bill Richardson — can ill afford for him to gain a victory in New Hampshire's first-in-the-nation primary as well.

"You said you would vote against the Patriot Act. You came to Senate, you voted for it. You said you would vote against the Iraq war, you came to the Senate and voted for" funding, she said.

"I think we should get into examining everybody's record," she said.

Obama's candidacy has soared on his pledge to bring change to Washington, and Clinton sought to blunt his advantage. "I think we're all advocating change," she said.

Edwards, second-place finisher in Iowa, worked throughout the debate to align himself with Obama as an advocate for change in Washington, and described Clinton as a defender of the status quo.

"Every time he speaks out for change, every time I fight for change, the forces of status quo are going to attack," Edwards said.

"I didn't hear these kind of attacks from Sen. Clinton when she was ahead," he said. "Now that she's not we hear them."

But with the first primary only three days away, Clinton had little time to make the case she hoped would knock Obama off stride.

Challenged on healthcare, Obama acknowledged that he has said if he were designing a system from scratch, he would set up a single-payer system that would give coverage to all. He said that is impractical, given the current system in which so many people receive their insurance from employers.

Obama's healthcare plan relies on government financial incentives and cost-cutting to help the uninsured afford coverage. But unlike Clinton and Edwards, he does not require adults to buy coverage or pay a penalty if they fail.

"I disagree with that because as I go around, I don't meet people who avoid getting healthcare. The problem is they can't afford it," he said.

The opening moments of the debate produced agreement on Obama's summertime statement, controversial at the time, that he would take action against terrorist leader Osama bin Laden if he had actionable intelligence that he was hiding in Pakistan and the government there did not act.

"As much as possible," the United States should seek agreement from Pakistanis, Obama added.

Edwards agreed. "If I as president of the United States know where Osama bin Laden is I would go get him," the 2004 Democratic vice presidential nominee said.