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The upcoming Fox News/Google debate Thursday in Florida comes at a time when growing numbers of voters are becoming so frustrated with President Obama they are vowing to vote against him. But, as demonstrated in a new national poll out Wednesday, Americans are still far more interested in voting against Obama than voting for anybody in the current Republican field.

At the debate, the candidates will have a chance to reveal that political X factor -- the quality that makes them not just competitive, but presidential. But while the right candidate may already be on stage, polls suggest voters haven't fallen in love with anybody yet.

"The voters know they want to vote against President Obama. They are still seeking who that person is going to be," said David Avella, president of Republican recruiter GOPAC.

A McClatchy-Marist poll starkly demonstrated a peculiarity in the 2012 race that has been evident for months. With Obama facing record-low approval ratings, the poll showed a majority of voters definitely plan to oppose Obama next November, by a wide 49-36 percent margin. Among independents, the margin is 53-28 percent. Yet none of the declared candidates led Obama in head-to-head matchups.

Former Massachusetts Gov. Mitt Romney did best, trailing Obama by 2 points. Texas Gov. Rick Perry was trailing by 9 points, and Minnesota Rep. Michele Bachmann was trailing by 13 points. The survey of 1,042 adults had a 3 percent margin of error.

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Thursday's debate is an opportunity for the candidates to assuage concerns about their perceived weaknesses and seize on any opening they can.

Perry has made a big play to shore up his foreign policy credentials in recent days. He showed up on the outskirts of the U.N. General Assembly Tuesday and lobbed searing accusations at Obama for his handling of the Middle East peace process. Perry, standing alongside Jewish leaders like Israeli politician Danny Danon and American Orthodox rabbi Pesach Lerner, effectively blamed the administration for the Palestinian bid for statehood at the U.N. which the administration is trying to short-circuit.

At the same time, Perry is also going hard against Obama directly, launching a new ad on Thursday that hits the president with the refrain on "zero jobs" in August while touting his own record in Texas.

Avella said the key to the race is relatively simple -- "the candidate who best articulates how we're going to create jobs is ... going to be our nominee." But he said for Perry, the governor has to also show he can build a coalition of supporters, and not just those in the South and West.

Meanwhile, Perry continues to deflect questions about his stance on Social Security as well as his record as governor, including the state's highest-in-the-nation execution totals and his signing of an order mandating girls receive a potentially cancer-preventing injection known as the HPV vaccine. While Perry says he had the health of girls in mind, others call it an executive overreach and point to his ties to the manufacturer of the drug.

But the HPV debate has proved troublesome for Bachmann as well -- who at the last go-round hammered Perry over the issue but then subsequently made questionable claims about the side effects of the drug.

Her handling of the controversy served to highlight one of the chief criticisms of Bachmann -- that she is quick to make accusations and claims that don't always withstand scrutiny, and then slow to walk back the original claims.

Her former campaign manager, Ed Rollins, told Fox News that despite her debate performance the HPV issue "hurts her at this point in time."

Rollins said that dispute will fade and argued Bachmann still has a chance at pulling ahead. He confirmed the Bachmann strategy is centered on winning the leadoff Iowa caucuses, while acknowledging that Perry's entry into the race in August knocked her off her game.

"She can win Iowa. If she wins Iowa, she's still in this race," Rollins said.

Romney, meanwhile, is looking a bit better than he was after Perry entered the race. A recent Gallup poll showed him trailing Perry by 7 points whereas he stood far above the rest of the field before Perry's entry. The ex-governor has repeatedly faced scrutiny for overseeing Massachusetts' health care overhaul which the Obama administration mischievously has cited as a model for the national overhaul -- widely unpopular among conservatives. And his reputation as an ideologically flexible moderate poses challenges in certain GOP primary states.

Still, Romney has stressed his experience in the private sector over his one term in office as governor -- at a time when jobs, or lack thereof, are seen as the most important issue in the 2012 race. Past debates have served as a platform for Romney and Perry to contrast their respective records on jobs.

While Perry cites Texas' record as the nation's premier job creator over the past two years, Romney and Texas Rep. Ron Paul, another contender, have sought to minimize Perry's role in the creation of those jobs. But while Romney cites his record with private equity firm Bain Capital, Romney's critics highlight the job cuts that occurred under his watch.

Romney, in Florida ahead of Thursday's debate, has also latched onto Perry's calling Social Security a "Ponzi scheme," which Romney says scares voters. He said Wednesday that three models currently exist -- Obama's, which is to do nothing; Perry's, which is to allow the states to decide; and his, which is to slow down inflation on health care and recalculate benefits for high-income recipients, all while not raising taxes.

"Tens of millions of Americans are relying on Social Security. I want to protect it. I want to save it. I think it's a good thing," he said, noting that the program initiated under Democratic President Franklin Roosevelt also won support from Ronald Reagan.

Perry's camp countered that Romney has "failed to issue a specific plan on Social Security," claiming Perry is dedicating to fixing the program for future generations.

As for the rest of the pack, the candidates have all demonstrated a flare on stage at recent debates but have not broken out of single digits in most polls. They include Paul, businessman Herman Cain, former House Speaker Newt Gingrich, former Pennsylvania Sen. Rick Santorum and former Utah Gov. Jon Huntsman.

For Paul, he is considered one of the fathers of the Tea Party movement for his vanguard approach to the Federal Reserve and debt reduction. But Paul, who faced criticism from viewers for shrugging at the notion Iran could gain nuclear weapons, is considered offbeat on foreign policy.

Cain, an established businessman who's had his hands in several successful enterprises, most notably as CEO of Godfather's Pizza, is viewed as a worthy adversary on economic issues. He is still struggling to establish his credentials on foreign policy, and often his quips are seen as substitutes for substance.

Santorum has been well-regarded on foreign policy and social issues, and won his state's straw poll over the weekend. But his objective must be to provide voters with something that gives them confidence he could take the economy by the proverbial horns and turn it around.

Huntsman also has a strong combination of government and business experience as well as demonstrable economic and foreign policy records, but is viewed by many as too willing to compromise, a failing in the current political climate. Gingrich, known as the brain of the group, is called too undisciplined but offers big ideas couched in grumbling over media coverage.

Also appearing in a debate for the first time since May is former New Mexico Gov. Gary Johnson, a libertarian-leaning Republican who emphasizes his exercise routine as much as his candidacy despite having a record in New Mexico worth noting. He stressed that record in a statement Wednesday, noting he vetoed hundreds of bills as governor and vowing to "veto any spending legislation that exceeds revenue" if elected president. He said he would submit a balanced budget in 2013.

Each of the candidates faces a big challenge, particularly since the format of Thursday's debate empowers voters to ask the questions. Through an arrangement between FoxNews.com and Google, who joined together to host the debate with the Republican Party of Florida, thousands of questions were submitted via text and video on YouTube.com/foxnews. About a dozen of the submissions will be asked during the debate, and it is the opportunity for the candidates to shine at least in the eyes of the individual questioner.