US President Barack Obama's approval rating climbed to 47 percent in a new poll released Wednesday, closing on a level which could help him run a competitive reelection bid next year.

In a Quinnipiac University poll, Obama's approval rating rose from 41 percent in October, and the president held leads of five to 16 points over potential Republican challengers in the 2012 election.

"President Barack Obama appears to be improving in voters' eyes almost across the board," said Peter Brown, assistant director of the Quinnipiac University Polling Institute.

"He scores big gains among the groups with whom he has had the most problems -- whites and men. Women also shift from a five point negative to a four point positive," Brown said.

The poll was conducted between October 25 and 31, following the death of Libyan leader Moamer Kadhafi and the release of some slightly more hopeful US economic data, which could have boosted Obama's standing.

While Obama's approval stood at 47 percent -- one point higher than his rating in a CBS/New York Times poll last month -- his disapproval rating stood at 49 percent.

Incumbent presidents generally need to keep their approval ratings in the high 40s or preferably over 50 percent to stand a good chance of winning a second term.

"The movement allows the White House a sigh of relief, for the president's approval had been stuck in the low 40s for some time," Brown said.

The poll also offered a snapshot of the Republican nominating race to take on Obama in the 2012 election.

It found that former pizza executive Herman Cain led the field with 30 percent, followed by former Massachusetts governor Mitt Romney at 23 percent, former House speaker Newt Gingrich at 10 percent and Texas Governor Rick Perry at eight percent.

But the poll was conducted before stories broke that Cain had been the subject of sexual harassment complaints in the 1990s, which could dent his political prospects.

The survey suggested that Obama has improved his prospects against potential Republican rivals, leading Romney 47 percent to 42 percent, Perry by 52 percent to 36 percent and Cain by 50 percent to 40 percent.