Former Massachusetts Gov. Mitt Romney remains in first place, the Quinnipiac Poll reported Wednesday. But his support remains where it was in a June poll at 25 percent, while Bachmann has moved up from 6 percent to 14 percent.
Recent polls in Iowa have showed Bachmann, who represents neighboring Minnesota in Congress, in a tie with Romney in the state that holds the first caucuses.
The only other names in double digits are two who have not declared, former Alaska Gov. Sarah Palin at 12 percent and Texas Gov. Rick Perry at 10 percent.
Peter A. Brown, assistant director of the Quinnipiac University Polling Institute, said it is still early in the race.
"The question about Rep. Bachmann is whether she is the flavor of the month, like Donald Trump was for a while, or does she have staying power?" Brown said.
The poll also showed President Obama would get at least 50 percent of the vote against Bachmann, Palin or Perry if the election were held today. He would beat Romney with 47 percent of the vote to 41 percent.
Quinnipiac surveyed 2,311 registered voters by telephone July 5-11, including 913 Republicans. The margin of error is 2 percentage points for all voters and 3.2 points for Republicans.