I would be careful about declaring the presidential contest "a whole new race" following Wednesday's debate. Polls show that most voters have made up their minds, and some, due to early voting, have already cast their ballots. One good night for Mitt Romney does not turn the world upside down.

But make no mistake, it was a very good night for Romney - and a bad one for President Obama. This election wasn't a done deal before the debate, and it certainly isn't now.

The immediate impact of Wednesday's encounter was to buoy the spirits of Republicans who feared that their chances of taking the White House were irretrievably slipping away. Blunders by Romney and his campaign advisers had begun to unnerve GOP bigwigs and depress the party faithful. Conservative commentators wondered whether Romney had it in him to recover from his missteps, the worst of which - his "47 percent" rant - threatened to become a rhetorical albatross.

Anyone who wondered how Romney would explain his cold dismissal of nearly half the country is still wondering. No one pressed him on that, not debate moderator Jim Lehrer and not Obama. I'm still shaking my head.

In any event, the gloom that had enveloped the Republican camp has suddenly lifted. Now it's Democrats who are answering questions about their candidate's performance on the stump.

I don't know why Lehrer decided to take such a laissez-faire approach, but he gave both candidates the same latitude. Only one took advantage.

Perhaps many people, like me, had forgotten that during the 2008 campaign Obama never showed the kind of mastery in debates that he routinely demonstrated in campaign speeches. He out-debated John McCain, but during the primaries he was often bested by Hillary Clinton. She wasn't able to use those debate performances to move the needle. Now we'll see whether Romney can.

Much has been made of the contrast in body language. Obama, frankly, did all the things they tell you not to do when you're on television. He looked down a lot. Perhaps he was taking notes, but the effect was to make him seem to withdraw. When Romney was talking, sometimes the president nodded as if in accord, even at moments when Romney was saying things with which Obama clearly does not agree. Romney, on the other hand, looked straight at Obama when the president was talking. Romney sometimes seemed a bit hyper - almost overcaffeinated, though he does not use caffeine because of his faith. But he was always engaged.

Obama is a reflective speaker who pauses frequently to find the right word. Romney just spits it out. Either style can be effective. The real problem last night was what went unsaid, or unasked.

During the long wrangle over taxes, for example, Obama tried to drive home the point that Romney's plan doesn't add up - that it's impossible to close enough loopholes or limit enough deductions to recapture the revenue that would be lost because of lower income-tax rates. But Obama never asked the simple questions that Romney has refused to answer: Which loopholes would you close? Which deductions would you limit?

Obama had to anticipate that Romney would try to draw him into a brawl, and he may have decided to be presidential, to remain above the fray. It's possible to maintain such a posture on the campaign trail, but I don't think you can bring it off in a debate. The fray is the whole point of a debate.
It wasn't a disaster, from Obama's point of view, but it was a bad night and a missed opportunity. Even if the debate had been no better than a draw, Obama probably could have spent the rest of the campaign running out the clock. Now Romney and the Republicans have a new spring in their step. They believe they can win.

The basic outline of the contest - the president holding a modest lead and superior electoral college prospects - remains unchanged. Obama has bounced back before. But no, this ain't over.

Eugene Robinson is a Pulitzer Prize winning columnist and writes for The Washington Post. He can be reached at eugenerobinson@washpost.com.