Correction: An earlier version of this story misstated where independents stand on “handling taxes.” The story has been corrected.

After a difficult summer and a contentious fall, President Obama’s job-approval ratings are showing signs of improvement — a crucial indicator of his reelection chances as he seeks to overcome voters’ doubts about his economic stewardship.

A new Washington Post-ABC News poll finds that Americans are still broadly disapproving of Obama’s handling of the economy and jobs, the top issues, but that views of his overall performance have recovered among key groups, including independents, young adults and seniors.

At the same time, the public’s opinion of Republicans in Congress has continued to deteriorate, potentially putting the president in a position to benefit politically from his standoff with the GOP-led House over extending the payroll tax cut.

Obama’s job-approval rating is now at its highest since March, excluding a temporary bump after the killing of Osama bin Laden: Forty-nine percent approve, and 47 percent disapprove.

Perhaps more important to the battle over the payroll tax cut, Obama has regained an advantage over Republicans in Congress when it comes to “protecting the middle class.” In the new poll, 50 percent say they trust Obama on this issue, compared with 35 percent who choose the GOP — a major change from last month, when the two sides were more evenly matched on the question.

On taxes, Obama has improved since early October, while public trust of the GOP has slipped. Forty-three percent now side with Obama on the issue, and 41 percent with Republicans in Congress.

Obama continues to face major hurdles on the overarching issues of the economy and job creation, with independents divided about evenly between the president and Republicans in Congress.

Still, his rise suggests that the White House’s new tactics in recent months — to adopt a more populist tone and to challenge Republicans aggressively over taxes and income disparities — may be shifting the national political landscape back to Obama’s favor.

And it comes with an outburst of optimism among Democrats, 72 percent of whom now say Obama will win reelection, up from 58 percent who thought so in October. Americans overall believed by a wide margin in October that a Republican would beat Obama next year, but they are evenly split in the new poll.

The president is locked in a dead heat in a potential general-election contest against former Massachusetts governor Mitt Romney, the new poll finds, with each winning support from 47 percent of registered voters. The two have been closely matched all year and are now about even among crucial independent voters.

The president leads a potential race against former House speaker Newt Gingrich (Ga.) by 51 to 43 percent among registered voters — in part because of an eight-point edge among independents.

Although the hypothetical general-election matchups are little changed from previous polls, overall, the results suggest that Obama may have found a way to navigate the politics of a sour economy — a development that seemed unlikely after the bitter debt-ceiling debate last summer. Then, he and his aides played an intimate role in negotiations, only to share public blame with Congress when things turned ugly.

In September, Obama laid out a jobs plan, which included extending the payroll tax cut, and proceeded to hammer the GOP in a series of campaign-style speeches, many of them in election battleground states.

Now, while lawmakers remain embroiled in partisan fights over budgeting and taxes, Obama may be benefiting from his perch above the fray.

In contrast to his improving numbers, public approval of Republicans in Congress has dipped to 20 percent. Democrats in Congress do not fare much better, dropping to a 27 percent approval rating.

And the discontent with Congress has reached historic levels. For the first time in available Post-ABC data back to 1994, a majority of Americans disapprove of the way both Republicans and Democrats in Congress are doing their jobs.

Among independents, 74 percent have negative views of Republicans in Congress, 71 percent disapprove of the legislative body’s Democrats, and 60 percent rate both poorly.

But the parties aren’t losing out just with the middle — their respective bases are getting agitated. Democrats’ approval of their party’s representatives in Congress has slipped to 51 percent, down from 62 percent in April and 77 percent just after Obama took office. Republicans’ support for the GOP has cratered even faster, plunging from 63 percent in April to 38 percent in the new survey.

Even those Republicans who back the tea party movement have soured on the GOP. In the spring, 73 percent of tea party supporters approved of the Republicans in Congress. Now, 41 percent approve and 57 percent disapprove.

Obama may be benefiting from circumstances as well, with the jobless rate recently dipping slightly, to 8.6 percent. The new survey finds that most Americans are optimistic about their personal finances, even though gloom continues about the prospects for the national economy.

Top aides to Obama, both at the White House and in his reelection campaign, have begun to appear more confident in recent weeks.

Over the weekend, after Obama appeared triumphantly in the White House briefing room to cheer Senate approval of a two-month extension of the payroll tax cut, one senior official all but gloated to reporters that the politics of the economy had turned around, with the GOP suddenly on the defensive over taxes.

“If we get into mid-February and there are still hijinks going on, we don’t think that’s a bad playing field for us to engage in public debate about whether we are going to continue to cut taxes for workers,” the official said.

Several factors seem to explain the rise in Obama’s approval rating. He has recovered from single digits among Republicans, with 19 percent now approving of his job performance.

He remains mired below 50 percent among independents, with 44 percent approving and 51 percent disapproving. For the first time since May, he’s pulled about even with seniors, 48 percent to 49 percent, and strengthened among people age 18 to 29, 55 percent to 36 percent.

More than 40 percent of white, non-college-educated men approve of his job performance, a high since January.

The poll was conducted Dec. 15 to 18 among a random national sample of 1,005 adults. Results from the full survey have a margin of sampling error of plus or minus 3.5 percentage points.

Polling analyst Scott Clement contributed to this report.