US President Barack Obama's approval rating has surged over 50 per cent on the falling unemployment rate.
The poll by the Washington Post and ABC television on Monday found Obama topping the 50 per cent barrier, seen as a critical threshold for an incumbent seeking re-election, for the first time since Osama bin Laden was killed last May.
Pollsters said Obama's ascent comes as the US economic recovery appears to be finally taking hold, with voters appearing more confident and comfortable with his policies.
The latest US figures released last week found that the unemployment rate has fallen to 8.3 per cent, the fifth straight monthly decline since August, when it stood at 9.1 per cent.
The US president now holds a solid nine percentage-point lead over the frontrunner for the Republican nomination, Mitt Romney, in a hypothetical general election matchup, according to the survey.
Obama leads Romney 52 to 43 per cent among all Americans, and by a narrower 51 to 45 per cent among registered voters - his first time topping 50 per cent in a head-to-head matchup with Romney since July, the pollsters said.
But the president still has substantial work to do: Among the all-important independent voters likely to determine the outcome of the election, 47 per cent approve and 50 per cent disapprove of the way he is handling his job.
His approval numbers are much better than they had been a few months ago when they sunk as low as 34 per cent among swing voters.
As the Republican nomination battle grows more bitter and divisive, the public's view of Romney, seen as the clear frontrunner after back-to-back wins in Florida and Nevada, has soured, the poll found.
Fifty-five per cent of those who are closely following the campaign said they disapprove of what the Republican candidates have been saying.
Romney, a former Massachusetts governor and multimillionaire venture capitalist, appears to have been hurt by negative assaults launched by his rivals for the nomination, in particular former House speaker Newt Gingrich.
By more than two to one, respondents said the more they learn about Romney, the less they like him, while 57 per cent of those polled said they approved of most of what Obama's laid out in last month's State of the Union speech.
The poll of 1000 adults and 879 registered voters was conducted between February 1 to 4 and has a margin of error of plus or minus four percentage points.
Romney is hoping to carry the caucuses of Colorado and Minnesota to cement his claim on the Republican presidential nomination.
Polls suggest he should triumph easily in the western US state, where he scored 60 per cent in 2008, although there is a tighter race in Minnesota, where last-placed Rick Santorum is hoping to snatch a win.
