WASHINGTON -- President Barack Obama's national standing has slipped to a new low after his victory on the historic health care overhaul, even in the face of growing signs of economic revival, according to the latest Associated Press-GfK poll.

The survey shows the political terrain growing rockier for Obama and congressional Democrats heading into midterm elections, boosting Republican hopes for a return to power this fall.

Just 49 percent of people now approve of the job Obama is doing overall, and 44 percent like the way he handled health care and the economy. Last September Obama hit a low of 50 percent in job approval before ticking a bit higher.

His high-water mark as president was 67 percent in February of last year, just after he took office.

The news is worse for other Democrats. For the first time this year, about as many Americans approve of congressional Republicans as Democrats, 38 percent to 41 percent, and neither has an edge when it comes to the party voters want controlling Congress.

Democrats also have lost their advantage on the economy -- people now trust both parties equally on that, another first in 2010.

Roughly half want to fire their own congressman.

And it could get worse for Democrats: One-third of those surveyed consider themselves tea party supporters, and three-quarters of those people are overwhelmingly Republicans or right-leaning independents.

That means they are more likely to vote with the GOP in this fall's midterms, when energized base voters will be crucial amid the typical low turnout of a non-presidential election year.

The poll involved interviews with 1,001 adults nationwide.