WASHINGTON -- The presidential debate at Hofstra University Tuesday night presents an opportunity for President Barack Obama to redeem himself and for his challenger Mitt Romney to press his advantage, political analysts say.
The pressure is on Obama after he stumbled with a subpar performance in the first debate, allowing Romney to reset his then-struggling campaign and to win a tie in the polls.
Vice President Joe Biden's aggressive performance -- Republicans say embarrassing for his laughs and constant interruptions -- in the debate with Romney running mate Paul Ryan, stopped that surge. Now it's up to Obama to try to turn things around with three weeks to go, analysts said.
"Obama absolutely can redeem himself," with a strong performance, passion for his views and a push-back against Romney, said David Birdsell, Baruch College public affairs dean.
Romney can continue the momentum from the first debate, Birdsell said, if he keeps the focus on "what he is going to do in the next term," not the different positions he has taken.
Tuesday night's debate, with its distinctive town hall format and large TV audience, will be a challenge for the candidates' second face-to-face encounter, said Mississippi State's Mark Goodman, a scholar on town hall debates.
Unlike in the other two debates, Obama and Romney can roam around a platform at the Mack Sports Complex as moderator Candy Crowley of CNN taps 10 to 15 undecided Nassau County voters to ask questions about anything from jobs, taxes and deficits to Libya and China.
Obama and Romney will be judged not just on their words, but on how they appear, Goodman said. "People really believe their eyes," he said.
Beyond those common issues, here are five challenges they each face.
Obama has admitted he had a "bad night" in the first debate. He can't afford another one.
Obama appeared as if he wanted a second term, but didn't want to campaign for it, said Michael Dawidziak, a Republican pollster from Bohemia, who as a campaign adviser saw the same thing happen to President George H.W. Bush in 1992.
"Look like you want to be there," Dawidziak advised.
Go on offense
Obama pulled his punches last time. He can't do that again either, Hofstra presidential scholar Meena Bose said. "He can't just play defense."
Obama admired Biden's feisty approach, aides said.
"I think you'll see somebody who is very passionate about the choice that our country faces, and putting that choice in front of voters," senior White House adviser Robert Gibbs said on CNN on Sunday.
Obama lost his presidential presence in the first debate.
"Obama walked into that debate with the presidency in his hand, but he came across as being weak," said Goodman.
Romney will raise leadership issues by pressing Obama on the deadly terrorist attacks on the U.S. embassy in Libya and the administration's shifting stories afterward.
On Tuesday night, Obama must have some answers, and appear both presidential and strong.
Connect with voters
Talking about policy, not people, won't cut it for Obama, analysts said. Tuesday night, he needs to display his star power and likability, an area where polls show he leads Romney.
Obama will have live voters in the hall to help him. "They are people with whom the audience members at home are going to sympathize. Engage them," said Birdsell.
Offer a vision
Obama hasn't said in a clear and effective way yet what his plans are for a second term and how it will help the American people, analysts said.
Yet he can build his answer on the best jobs report in 44 months and a Washington Post-ABC News poll Monday that showed 42 percent think the country is headed in the right direction, up 13 points since late August.
And, Dawidziak said, "He's got to be inspiring."
Don't overdo it
Romney came with an aggressive game plan in the first debate, but at times edged toward going too far, analysts said.
"He was very aggressive in the first debate, but you don't want to go overboard so people feel sorry for Obama," said Dawidziak.
Bose said Romney can be critical, but she advised, "Stay calm, energetic and positive."
After the first debate, twice as many people said their opinion of Romney improved as said it worsened, and fewer felt anxiety about a Romney presidency, the Post-ABC poll found.
Romney must make sure he doesn't lose that new footing with a gaffe or slip-up. Bose said, "Romney is beginning to be seen as presidential, and he should maintain that image."
A key Romney weakness is his likability. He trailed Obama by 2-1 on that score in the Post-ABC poll, which also highlighted voter concerns that he might favor the wealthy as president.
Romney has to appear at ease, and must work to soften his comments about the "47 percent" of Americans he said he can't reach because they depend on government.
"Nice touches make a difference," Bose said.
Plan of attack
Romney needs to keep undermining Obama's built-in authority and strength as a president, but focus on jobs and debt.
"He always had the economy, that was always a huge edge," Dawidziak said of Romney.
Yet Dawidziak said Romney should attack on one foreign issue: the administration's handling of the Sept. 11 terror attack in Libya that killed the U.S. ambassador.
Advance the deal
Romney's victory in the first debate has stirred up Republican enthusiasm, something that for a long time eluded him, the Post-ABC poll found.
Tuesday night, he must stoke those fires, but also continue to move to the middle to win undecided voters, analysts said.
"There is no closing the deal yet, but you can advance it," Dawidziak said. "Keep the pressure on."