DENVER - Wednesday's presidential debate was a tale of four candidates: the two men who stood on the stage and the two rivals seen for months on the campaign trail. There was no comparison.

Start with President Obama, who may have lost the debate in as lopsided a manner as any incumbent in recent times. Other incumbents have stumbled in their first re-election debates. Ronald Reagan in 1984 and George W. Bush in 2004 come to mind. Both had bad moments that cost them the debate.

Obama didn't lose because he had a few bad moments. Challenger Mitt Romney dictated both the tone and the tempo of the evening, at times acting as candidate and moderator. Obama fell behind in the opening minutes and never really found his footing. He lacked energy stylistically and he lacked crispness substantively.

'They have to recalibrate'

This wasn't the Obama seen in campaign commercials or in the daily scrum. Given his vulnerability due to the state of the economy, Obama and his advisers sought to define Romney before Romney could define himself. It seemed to work. The campaign attacked Romney for his work at Bain Capital, for not releasing his tax returns, for putting money in a Swiss bank account and in the Cayman Islands.

Obama mentioned none of that on Wednesday. It was as if he left his campaign's best attack lines in a folder backstage. Inexplicably, he never once mentioned Romney's "47 percent" comment -- his line that nearly half of all Americans pay no federal income taxes, that they see themselves as victims, that they're dependent on government and unwilling to take personal control of their own lives.

If none of those were worth talking about on Wednesday, why has Obama's campaign spent the last four months and hundreds of millions of dollars driving home that message?

Whatever the case, his performance left Democrats wondering what happened. As one Democratic strategist put it in an e-mail Thursday: "ughhh."

Tad Devine, another Democratic strategist, sent an e-mail with this assessment of the president's apparent strategy: "I assume they had a strategy not to engage or get too personal. He [Obama] was like he had been in many previous debates, but in these very different times, cool and calm is not as powerful as it once was. They have to recalibrate or risk being pushed aside by the new and improved Romney."

Romney, too, seemed disconnected from the candidate Americans have seen over the past year. On the campaign trail, he is awkward and wonky. Only in debates did he shine during the primaries, and on Wednesday he was back on comfortable ground.

'A reasonable man'

But who was the Romney Americans saw on Wednesday night? This was not the candidate who lurched to the right to win the nomination. This was not the nominee of a Republican Party that is more conservative than it was when conservative icon Reagan was president. This was moderate Mitt, the turnaround artist with a plan to fix the economy. As William Galston of the Brookings Institution put it: "Romney presented himself as a reasonable man -- neither an extremist nor an ideologue."

But in the aftermath of the debate, Romney will face questions about his agenda, including the one that the president did not force him to answer. Romney insisted that he does not have a $5 trillion tax-cut plan that would favor the wealthy, though independent analysts have said it would.

If that's not his plan, what is his plan? How much would it cost? And just how would he make the math add up? He refuted Obama's criticisms by deflection, not by engagement.

In the hours after the debate, Obama campaign advisers were insistent that they would tear into Romney for what he said and didn't say. Obama failed to make his criticisms stick in person.

Both sides believe the contrasts drawn favor their candidates. Obama's team sees Romney on the wrong side of public opinion on Medicare, on dealing with the deficit and on protecting the middle class. Romney's team argues that Obama is on the wrong side of public opinion in calling for higher taxes, more spending and more regulation.

Republicans were elated. They knew that a bad performance might have all but doomed Romney's chances of winning the election. Now they see a race joined again. Stuart Stevens, the Romney campaign's chief strategist and a target of considerable criticism over the past month, said: "I don't think [Obama] had a particularly bad debate. He has a bad record."

Democrats were sobered by the president's performance but believe fundamentals still work in Obama's favor. "Romney is a top-notch debater and the president had an off night," said Steve Rosenthal, a Democratic strategist. "Hopefully last night was a wake-up call to anybody on our side who had grown overconfident or complacent."

It will take some days for the impact of the debate to filter through the electorate. But for the moment, Romney far exceeded expectations, and for now that has made this a different contest.


Vice President

• 8 p.m., Oct. 11, Centre College, Danville, Ky.


• 8 p.m., Oct. 16, Hofstra Univ., Hempstead, N.Y.

• 8 p.m., Oct. 22, Lynn University, Boca Raton, Fla.