The public images of House Speaker John Boehner and Senate Republican Leader Mitch McConnell remain decisively in negative territory. Some 59 percent say the nation remains on the wrong track, while just 31 percent say it's headed in the right direction.
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Still, that 31 percent mark reflects a nine-percentage-point rise since last August. The brightening mood suggests an opportunity for both the White House and Congress to improve their own standing with tangible achievements, though Americans don't expect that to happen.
By 59 percent to 35 percent, more Americans say a government divided between the two parties doesn't work well for the country than say it does. In 1999, when Bill Clinton was president and Republicans controlled Congress, those proportions were essentially reversed.
Some 45 percent say Mr. Obama has been too stubborn in dealing with Republicans in Congress; 55 percent say the same about the Republicans.
Mr. Obama enjoys solid support for two of his controversial recent executive actions. A 52 percent majority approves his action on immigration, which Republicans have sharply criticized and vowed to roll back. Fully 60 percent approve his decision to end a 50-year U.S. policy of isolating Cuba and normalize relations.
At the same time, Republicans hold the upper hand on the Keystone XL pipeline, which the president has so far declined to approve. By two to one - 41 percent to 20 percent - Americans say the pipeline should be built.
As attention turns to the 2016 presidential race, the poll has a cautionary note for Republicans. Two of the party's best-known potential candidates, Mitt Romney and Jeb Bush, are viewed more negatively than positively by double-digit margins. The Democratic front-runner, Hillary Rodham Clinton, is viewed more positively than negatively by eight percentage points.
The poll of 800 adults, conducted by telephone Jan. 14-17, carries a margin for error of 3.46 percentage points.
—By CNBC's John Harwood. Follow him on Twitter: @JohnJHarwood