Obama's rating has been in the 50-percent range most of the time since his re-election and the new high in the three-day rolling poll coincides with the aftermath of the Dec. 14 mass school shootings in Newtown, Conn., Gallup said.
The poll results were released Thursday.
Obama is in the midst of negotiations with House Speaker John Boehner, R-Ohio, over a solution to the looming "fiscal cliff." Gallup polls indicate Americans give Obama higher marks for his handling of the situation than they do Boehner.
In the latest three-day average of Obama's job-approval rating, 91 percent of Democrats, 54 percent of independents and 16 percent of Republicans OK'd the job he is doing.
The rating among Democrats was unchanged from last week. The ratings among independents and Republicans increased from 47 percent and 9 percent, respectively, the Princeton, N.J., polling agency said
Results are based on nationwide telephone interviews with 1,605 adults conducted as part of Gallup Daily tracking Monday through Wednesday. The margin of error is 3 percentage points.