Voters also are divided on whether Obama should be re-elected, 47 percent in favor to 49 percent against, results of the Quinnipiac University poll released Wednesday indicted.
The results were just within the margin of error of 2.1 percentage points.
Among Republicans, former Godfather's Pizza Chief Executive Officer Herman Cain leads the party's presidential primary field with 30 percent, followed by former Massachusetts Gov. Mitt Romney with 23 percent, former House Speaker Newt Gingrich with 10 percent and Texas Gov. Rick Perry with 8 percent, results indicated. None of the other candidates topped 7 percent.
Obama also improved in matchups against potential Republican nominees, the Hamden, Conn., university poll indicated.
Obama had a 47 percent-to-42 percent lead over Romney and a 52 percent-to-36 percent edge over Perry, both up from last month, results indicated. The president had a 50 percent-to-40 percent lead over Cain and a 52 percent-to-37 percent edge over Gingrich, in a first-time hypothetical tilt.
Results are based on nationwide telephone surveys of 2,294 registered voters Oct. 25-31. The margin of error for the overall poll was 2.1 percentage points. The Republican primary questions involved 869 registered voters and had a margin of error of 3.3 percentage points.