WASHINGTON -- If Mitt Romney is going to change the trajectory of aclose race that is bending in President Obama's direction, his bestopportunity will be during 90 minutes on a Denver stage Wednesday night.

Obamahas opened a modest advantage over Romney since the politicalconventions ended last month, especially in the battleground states. Butas the presidential rivals prepare to face off in the first of threedebates, a USA TODAY/Gallup Poll shows Obama with vulnerabilities andRomney with assets - even on the question of whether Americans havebecome too dependent on the government.

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The question: Can theRepublican challenger seize on those openings? If he fails - and headmittedly has struggled since clinching the GOP nomination in thespring - his path to victory over the final four weeks of the campaignbecomes much steeper.

"The vast majority of viewers tune in tothese debates to cheer their candidate on; they've made their decisionand want that decision confirmed," says Mitchell McKinney, an associateprofessor at the University of Missouri who studies presidential debatesand political communication. But there also will be viewers who areonly "weakly committed" to a candidate "and still need some persuading."

Almosteight in 10 Americans in the USA TODAY poll say there's nothing eithercandidate could say or do in the debates that would change their mindsabout their vote. Still, one of five say the debates could sway them -including 24% of Obama supporters and 18% of Romney supporters.


Those "persuadable" voters call for more specifics, lessrhetoric and fewer attacks. "Act more like four years ago," onerespondent said in response to an open-ended question included in thesurvey. Others who are leaning to Romney but open to Obama's case citedparticular issues, from doing more on the environment to saving thecoal industry. And a tall order: "Come up with all the answers for allthe problems."

Thedebates are a chance for Obama to win back the vote of Elizabeth Gower,49, of Tacoma, Wash. "Four years ago, my husband and I voted for Obama,and I think it was awesome that he got elected," she said in afollow-up interview with USA TODAY. "But as far as I'm concerned, he'sblown it." She worries that the Affordable Care Act the president signedinto law may subject her family to fines because they don't have healthinsurance and can't afford to buy it. She'd like to hear him on that.

Voterswho were leaning to Obama but open to hearing from Romney volunteeredthat Romney should show that he would focus on the concerns of peoplelike them. "He needs to help the middle class instead of keep helpingthe rich," one said in the survey. Several said they'd like to hear notonly that he would repeal the health care law but also what he would doin its stead. "Just say what he would do as president," one advised.

"It'sOK that he was a businessman and very wealthy, but I think he should behonest and open about that," Paul Rayman, 24, the operations manager ata distribution center in Indianapolis, said in a follow-up interview.He was put off by Romney's comment at a campaign event that students whocan't afford college should borrow money from their parents. "That wasreally laughable for a lot of people," Rayman says, and as he sees it, asign Romney doesn't understand the tough economic times many face.

"He needs to say he would in office seek out the opinions of others on how to address those concerns and understand," he says.

Thenthere's that damaging "47%" video. For weeks, Romney has been forced tospend time and air ads aimed at repairing damage from comments he madeon a secretly taped video at a fundraiser in May, posted online by theliberal Mother Jones magazine. In them, he described 47% ofAmericans as "victims" who are dependent on government and unwilling totake responsibility for their lives. Obama jumped on the comments asharsh, inaccurate and unpresidential.

Despitethe negative fallout, Romney's general point resonates with manyvoters. By 2-1, 64%-33%, those surveyed agree that Americans are toodependent on the federal government. A solid majority, 57%, say thegovernment is trying to do too many things that should be left toindividuals and businesses. One-third, 34%, think the government shoulddo more to solve the country's problems.

Romney's weaknesses onother fronts has made it difficult for him to tap that support for aless expensive and less intrusive government. His favorable-unfavorablerating is an anemic 47%-48%. The biggest personal shortcoming found inthe survey is the belief that he doesn't understand the problemsAmericans face in their lives.

One critical task for him is to convince them that he does.

Atthe same time, he needs to be on the attack against Obama. "He has tomake the case that the president's policies are directly responsible forthe bad economy," says Brett O'Donnell, a Republican consultant whoadvised Romney during some of the GOP primaries. "He's got to stay onoffense throughout the entirety of the debate."

Why they're undecided

MostAmericans surveyed like Obama. His favorable-unfavorable rating is55%-44%, his best standing this year. By 20 percentage points, they sayhe understands better than Romney the challenges of their lives. Bysmaller margins, they say he is more likely to share their values, to bea strong leader, and to keep his campaign promises - all assets in apresidential contest.

But when it comes to handling the issue theysee as most important - the economy - they remain unconvinced Obama isup to the job. A majority of those surveyed, 52%, predict the U.S.economy won't be better in four years if he wins a second term; 40% sayit will be worse.

Romney continues to have an edge when it comesto managing the economy - albeit a smaller one than he had before monthsof Democratic ads attacking his record at Bain Capital - and onhandling the federal budget deficit. If he is elected, 50% of thosesurveyed predict the U.S. economy will be better in four years; 35% sayit will be worse.

John Davis, 69, a retired chef from Reading,Pa., is an undecided voter because of his mixed views of bothcandidates. "I want to hear some kind of positive answer of how they'regoing to bring our country back together again," says Davis, who wascalled in the poll. "Romney sounds good on the economy, but he seems alittle lean on diplomatic issues, foreign policy issues. Obama soundsgood on foreign policy, but he's lousy with our economics. So I'm stillup in the air."

Obama has a 26-point advantage when it comes tohandling social issues such as same-sex marriage and abortion, and asignificant one on foreign affairs and handling terrorism. On healthcare, energy, Medicare and taxes, his edge over his challenger is insingle digits.

His approval rating has risen to 51%, the firsttime a majority of Americans have approved of the job he's doing aspresident since the brief boost he got after the killing of Osama binLaden last year. In the poll, the president's narrow lead nationwideexpands a bit in the 12 swing states but is still in single digits. (Theswing states: Colorado, Florida, Iowa, Michigan, Nevada, New Hampshire,New Mexico, North Carolina, Ohio, Pennsylvania, Virginia andWisconsin.)

If Romney needs to use the debates to convince votershe understands their lives, Obama's task is to convince them he can betrusted to make those lives better.

"With an incumbent presidentin a debate, the principle question is: Should you be re-elected? Do youdeserve four more years?" McKinney says. "Obama has to go beyond hismessage of 'it could be worse.' He needs to try to resurrect some of the'hope' message that it will get better."

What history has shown

Debates can be powerful.

Tenof the past 13 presidential elections have included televised debates.In three of them (1960, 1980 and 2000), the eventual winner went intothe first debate trailing in the Gallup Poll and came out of the lastone ahead. In two more (1976 and 2004), the eventual winner lostsignificant ground during the debates. That opened an opportunity forthe underdog in the campaign's final days, although in the end it didn'tchange the outcome.

Debates can't take a runaway race and make ita contest. In 1984 and 1996, popular incumbents Ronald Reagan and BillClinton swept to easy victories over Walter Mondale and Bob Dole. In2008, the nation's financial collapse, not the debates, defined thecampaign's final weeks and contributed to Obama's victory over JohnMcCain.

When the contest is relatively close, especially if one ofthe candidates isn't well-known, the debates can narrow a race or evenswing it.

Consider the impact in two of the three most recent elections:

In 2000, Al Gore went into the first of three debates leading GeorgeW. Bush by 8 points. After faceoffs in which his demeanor, hisexaggerated sighs and even his makeup drew criticism, Gore trailed Bushby 4 points after the last one. Gore ended up narrowly winning thepopular vote but losing the Electoral College, a split decision thatpresumably would have been avoided with a wider lead.

The lead inthe race also switched after the debates in 1960 and 1980, two contestswith iconic debates. John Kennedy's appeal over a pale, sweaty RichardNixon in 1960 stands as an object lesson for politicians in thetelevision age. In 1980, Ronald Reagan's reassuring mien in his onlydebate with then-president Jimmy Carter - and his closing "are youbetter off?" query to voters - gave him a crucial boost.

In 2004, John Kerry went into the first of three debates trailingBush by 11 points; he came out of the last one 3 points behind. Kerryfailed to get it closer. On Election Day, Bush won a second term by 3points.

This time, Americans by 57%-33% expect Obama to do abetter job in the debates. Even 17% of Romney voters predict Obama willprevail; just 2% of Obama supporters expect Romney to do better.

SteveElmendorf, a Democratic veteran who was Kerry's deputy campaignmanager, sees parallels this time with the 2004 race and calls thedebates critical. "There is a very small group of undecideds in thiselection, and maybe they won't watch all the debates," he says. "But myguess is their opinions will be moved by the debates.

"Romney is behind, and he needs to change the dynamic. His next opportunity, his last opportunity, is these debates."