Losing ground to Republican Mitt Romney on a host of issues, President Barack Obama faces a serious challenge to put his re-election bid back on track when the two men face off on Tuesday in their second debate.
Obama's passive performance in their first debate two weeks ago and Romney's subsequent surge have raised expectations for a more fiery encounter at New York's Hofstra University.
The Democratic president's team has been encouraged by the feisty performance of Vice President Joe Biden last week in his debate against Republican vice presidential nominee Paul Ryan.
Now, with Romney having virtually erased Obama's lead in national polls just three weeks before the November 6 election, Obama is hoping to take advantage of the town hall-style format in Tuesday's debate to make a direct pitch to voters.
Obama is likely to pitch his economic vision, which focuses on a tax breaks for the middle class and tax increases for the wealthy. Romney has called for across-the-board tax cuts and sparred with Obama over whether such a plan would add to the nation's debt problems.
On Sunday, Reuters/Ipsos surveys of likely voters indicated Romney had closed the gap or overtaken Obama in the past two weeks on a range of issues - from who would be better at creating jobs to dealing with taxes and Iran's nuclear ambitions.
The pressure is now on Obama, who has acknowledged he was "too polite" in that debate, to be more confrontational without appearing strident or desperate. For Romney, the task is simply to turn in another sure-footed performance that keeps the Republican momentum rolling.
"Obama can't afford another really bad debate performance, he won't have time to recover," said Bruce Buchanan, a political scientist at the University of Texas. "He's up against it now."
Obama often displays that passion on the campaign trail, comfortably hammering Romney with an easy style. Whether he can do so in the town-hall format of the debate, where undecided voters will ask questions of the two candidates, is an open question.
The intimate setting of that format sometimes restrains candidates from being too aggressive as they focus on questions from individuals rather than a moderator.
"You don't want to be too nasty in front of those voters, you need to have to have your empathy antenna up," said Dante Scala, a political scientist at the University of New Hampshire.
But the change in atmosphere from a stilted one-on-one standoff could make Obama "feel more at liberty to be expressive, less somber," Buchanan said. "He's very good at using crowds in a jocular way to attack his opponent. He does that every day on the stump."
A Reuters/Ipsos daily online tracking poll on Sunday showed Obama leading Romney by 1 percentage point, 46 to 45, down from a 3-point Romney lead last Thursday - a possible sign that the Republican's surge after the first debate could be running out of steam.