A new Gallup poll released just hours before the second presidential debate shows Mitt Romney widening his national lead over President Obama -- underscoring what's at stake for Obama as he tries to regain lost ground in the wake of a lackluster debate debut.
The poll of likely voters showed Romney leading 50-46 percent. It echoed the conclusion from a host of both national and battleground surveys conducted after the first Obama-Romney faceoff -- Romney is gaining ground and in some cases surpassing Obama in the polls.
Those same polls have shown most voters deemed Romney the winner of the Oct. 3 debate. After a pause in the schedule for the vice presidential debate last week, the pressure is on the president to recapture the momentum Tuesday night.
Going into the debate, Obama was upbeat.
"I feel fabulous," he told reporters.
The attitude belied the intensive preparation that is going into the president's performance. The debate at Hofstra University in Hempstead, N.Y., is an opportunity to check Romney's surge. And the president's team is making clear that Obama will have a more aggressive -- and more prepared -- approach this time.
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For Romney, Tuesday night is a chance to further erode Obama's lead in key battlegrounds. Romney's campaign has said little about how and whether the Republican nominee's style might differ Tuesday night, compared with the opening debate, though a second clear-cut victory for the Republican challenger could be a game-changer. A senior Romney adviser said the campaign anticipates a "more aggressive" Obama.
"We expect he'll launch one attack after another in an attempt to distract from his record and make up for his weak performance in Denver," the adviser said.
Both campaigns are stacking the debate hall with surrogates, who will be in place to spin the performances and try to get their version to dominate media coverage going into Wednesday.
Romney's campaign also announced a fresh endorsement Tuesday morning from Ross Perot, though the former presidential candidate is not on the surrogate list for the New York debate.
"We can't afford four more years in which national debt mushrooms out of control, our government grows, and our military is weakened. Mitt has the background, experience, intelligence and integrity to turn things around," Perot said in a written statement.
The latest polls continued to underscore how the race has changed since the first debate. A Quinnipiac University poll showed Romney cutting a 12-percentage-point gap in Pennsylvania to 4 points. The survey showed Obama leading 50 percent to 46 percent among likely voters.
A separate USA Today/Gallup poll showed Romney leading by 4 points across a dozen battlegrounds. Significantly, it showed Romney trailing by just 1 point among female likely voters -- a group that for months has solidly backed the president.
With their debate falling exactly three weeks before the Nov. 6 election, Obama will be fighting to hang on to small leads in many of the key swing states that likely will determine which man occupies the White House on Inauguration Day.
Beyond that, the debate at Hofstra University is seen as offering both candidates their best chance for a breakout moment with time running out. The race is shaping up as one of the closest presidential contests in recent U.S. history.
The candidates will take questions Tuesday on domestic and foreign policy from an audience of about 80 of the coveted uncommitted voters whom both campaigns are courting furiously. The town hall-style format makes it especially tricky for Obama to strike the right balance in coming on strong against Romney without appearing too negative to the audience and the tens of millions of Americans who will be watching on TV and online.
Since the last debate, the Obama campaign has claimed Romney is trying to fool voters by espousing more moderate positions on the issues. In a new Web video released Monday, the Obama campaign said Romney had not undergone an October conversion to more middle-of-the-road positions, but was trying "to pull the wool over voters' eyes before Election Day."
While the candidates were closeted with advisers preparing for this debate, their campaign machinery continued to grind on. Both sides released new ads, pushed at the grassroots level to lock in every possible voter, dispatched surrogates to rev up enthusiasm and kept running mates busy raising cash and campaigning in the most hotly contested states.
Obama's campaign turned to former President Bill Clinton on Tuesday to make the case against what it says is Romney's $5 trillion tax cut. Clinton appears in a Web video for the campaign, picking apart Romney's tax plan piece by piece, saying his approach "hasn't worked before and it won't work this time."
Obama's campaign, buoyed by recent encouraging news, also released a new battleground state ad Monday in which ordinary Americans talk about signs of economic progress.
Romney's running mate Paul Ryan took on the challenge, asserting in Ohio and Wisconsin that Obama had inherited a tough economic situation but made things worse.
With early voting already under way in dozens of states, including such battlegrounds as Ohio and Iowa, the candidates will have little time to recover from any missteps in the debate. Through Monday, either absentee or in-person early voting had begun in 43 of the 50 states.
First lady Michelle Obama mailed in her ballot Monday; the president plans to cast an in-person ballot in Chicago on Oct. 25 -- making history as the first incumbent to vote early.
Tuesday's debate audience of uncommitted voters was selected by Gallup, the polling organization. Moderator Candy Crowley of CNN will choose those who get to speak, after reviewing proposed questions to avoid repeats.
The final debate of the campaign will be Oct. 22 at Lynn University in Boca Raton, Fla., focusing on foreign policy.
The Associated Press contributed to this report.