Mitt Romney has opened a 5-percentage-point lead over President Obama in the 12 battleground states that are critical to determining the outcome of the 2012 election, according to a USA Today/Gallup poll released Monday.

Romney has 51 percent support among likely voters in the poll, compared to Obama's 46 percent. Among registered voters, Obama holds a slight 49 percent to 47 percent advantage.


The poll was conducted in Michigan, Florida, North Carolina, Virginia, Colorado, Nevada, New Mexico, Iowa, Ohio, Pennsylvania, Wisconsin and New Hampshire. There was no state-by-state breakdown of results.

The Obama campaign quickly disputed the poll's findings. It circulated a memo from pollster Joel Benenson calling the USA Today/Gallup poll “an extreme outlier” that defies “the trends seen in every other battleground and national poll.”

The memo pointed to past Gallup surveys that deviated from the final outcome, and said the current results underscore “deep flaws in Gallup’s likely voter screen.”

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It’s the latest in an ongoing controversy surrounding the viability of polls in this election cycle. Earlier, Republicans cried foul over what they said was a disproportionate amount of Democrats being included in surveys.

Most polling outlets survey only registered voters early in the cycle, but as Election Day nears, they prod for more information from voters to determine the likelihood that a registered voter will end up casting a ballot.

Because of that, many believe surveys of likely voters are more accurate than those that only survey registered voters. 

However, Gallup has noted that in some elections, as in 2008, “there was only a marginal difference between the vote choices of registered voters and likely voters,” while at other times, such as the 1996 presidential vote, “there was a much more substantial difference.”

Romney is buoyed in the USA Today/Gallup poll by female voters, who until recently had been strongly supportive of the president. 

Among likely female voters, Romney and Obama are tied at 48 percent. Obama still retains a sizable lead, 52 percent to 44 percent, over Romney among registered female voters.

The Obama campaign, however, also took issue with the poll’s findings among female voters. Benenson said that “on average, President Obama leads among women by 10.3 points.”

The USA Today/Gallup survey, however, is not the first poll to show Romney making impressive gains among women.

Earlier this month, in the immediate aftermath of the first presidential debate, a Pew Research survey showed Romney pulling even with Obama among women. That erased the president’s 18-percentage-point advantage in the previous Pew poll.

At the time, Pew's associate director of research, Michael Dimcock, told The Hill that Romney had seen “an across-the-board improvement on the way women feel” about him.

For Obama to win a second term, he will likely need to win about half of the electoral votes supplied by the 12 major electoral battlegrounds. 

The president won all of those states in 2008. A handful went for President George W. Bush in 2004 and could go either way in 2012.

Still, other polls have shown Obama holding a slight advantage when the swing states are broken down individually. 

The president’s leads in Michigan and Pennsylvania, in particular, will be difficult to overcome as those states have trended Democratic in recent elections.

This story was updated at 4:35 p.m.