Half of Americans now approve of U.S. President Barack Obama's job performance. His overall approval rating is 50 percent -- the highest it's been in 18 months, a Washington Post/ABC News poll released Monday indicated. It's also a jump of 9 points since December. Disapproval dropped to 44 percent.

The improving economy can take the credit, ABC News said. The most people since the start of the Great Recession -- 41 percent -- said the economy is doing well, and Americans who think the economy is good tend to back the president.

Also supporting Obama are 18- to 29-year-old millennials, whose approval of the president increased by 19 points this month, and men, whose approval climbed 11 points. Support among conservatives jumped 11 points, as well.

The Republicans may have taken over the House and Senate, but poll results indicate Americans trust Obama (40 percent) to fix the country's problems over Congress (36 percent). With margins of varying sizes, they said Obama has better ideas on how to help the middle class, create jobs and deal with climate change, among other issues. Forty-four percent of Americans said they don't expect the new Congress to be any worse -- or better -- than the previous one.

As for individual issues, about 61 percent were behind Obama's stance on the Keystone oil pipeline. The majority of Americans also support his free community college proposal, but many disagree with Obama's executive action on immigration -- in fact, 56 percent said they thought Congress should stop it.

Fifty-six percent of respondents said they thought the U.S. was headed down the wrong track, but that's the lowest the figure has been since fall 2012.

The poll noted its 50-percent approval rating was higher than other measures of the president's performance, such as Pew Research Center's finding of 47 percent last week, but pointed to an overall upward trend in popularity.

About 1,000 adults were polled Jan. 12-15. The margin of error was 3.5 points.