Washington ? People want Democrats to control Congress after this fall’s elections, a shift from April, according to an Associated Press-GfK poll released Saturday. But the margin is thin and there’s a flashing yellow light for incumbents of both parties: Only about one-third want their own lawmakers re-elected.

The tenuous 45 percent to 40 percent preference for a Democratic Congress reverses the finding a month ago on the same question: 44 percent for Republicans and 41 percent for Democrats. The new readout came as the economy continued showing signs of improvement and the tumultuous battle over the health care law that President Barack Obama finally signed in March faded into the background.

“To the extent that Democrats can focus on job creation rather than health care, they tend to do better,” said Jack Pitney, a political scientist at California’s Claremont McKenna College.

Democrats hold a 254-177 majority over Republicans in the House, with four vacancies, while Democrats control 59 of the Senate’s 100 seats, counting support from two independents. Despite those disadvantages, the GOP has gained political momentum in recent months and its leaders hope to win control of at least one chamber of Congress this November.

Compared with the last AP-GfK poll in April, the survey showed Republicans losing some support among married women, a key component of many GOP victories. Democrats picked up ground among young and rural voters.

“I’m a new Democrat,” said Harley Smithson, 51, of Baltimore, who said he had recently switched from the GOP. “I want to be with a party that’s for something instead of against everything.”

Even so, the poll underscores that the political environment remains ominous for Democrats.

Just 35 percent say the country is heading in the right direction, the lowest measured by the AP-GfK survey since a week before Obama took office in January 2009.

His approval rating remains at 49 percent, as low as it’s been since he become president.

Congressional Democrats win approval from only 37 percent, though congressional Republicans score an even drearier 31 percent.