The number of Americans with negative views of Mitt Romney has spiked in a new Washington Post-ABC News poll, compounding the former Massachusetts governor’s challenges as he tries to rally from Saturday’s big loss in South Carolina.

Among independents, Romney’s unfavorable rating now tops 50 percent — albeit by a single point — a first in Post-ABC polling back to 2006. Just two weeks ago, more independents had favorable than unfavorable views of Romney; now, it’s 2 to 1 negative.

Romney’s losses since a Post-ABC poll conducted between the Iowa caucuses and the New Hampshire primary are not limited to independents. The number of Democrats viewing him unfavorably is up 10 percentage points, and among his fellow Republicans, negative ratings have jumped from 18 to 32 percent. (Prior to his Iowa performance, Romney’s unfavorable number had been higher than 18, but hadn’t been in the 30s among Republicans since early 2008.)

Despite the slide, at 58 percent favorable among Republicans, Romney is as well reviewed as is his primary rival: In the new poll, 55 percent of rank-and-file Republicans give Newt Gingrich positive ratings. Some 34 percent view the former speaker unfavorably.

Nor does Gingrich fare better than Romney among independents, with Gingrich’s favorable numbers among independents at a low point back to the fall of 1996.

One reason Romney has been outperforming Gingrich in hypothetical match-ups against President Obama is due to independents. Now, both main Republicans are at a disadvantage.

Obama’s numbers in this poll, conducted Wednesday through Sunday, have tilted positive, both among all Americans (53 percent favorable) and among independents (51 percent favorable). The president’s favorability rating had, for the first time, dipped below the 50-percent mark last fall.

In a separate Post-ABC poll released last week, the president kicked off the year with a job approval rating of 48 percent, a bit of a recovery, but still below his recent predecessors at the start of their reelection years.

The new poll shows moderates now giving Obama a better-than-2-to-1 split, with 66 percent expressing favorable views and 31 percent unfavorable. Those are his best numbers in periodic polls back to April 2010.

For his part, Gingrich runs solidly the other way among these middle-of-the-roaders, at 20 percent positive, 58 percent negative. Romney, whom moderates rated about evenly throughout the fall and into early January, are now about 2 to 1 negative: 27 percent hold favorable views, 52 percent negative ones.

One group that continues to elude Obama in his moderate resurgence on favorability is whites with annual household incomes under $50,000. Since December, whites with higher incomes are up eight points in favorable impressions of the president; those under the $50K threshold are basically unmoved at 40 percent favorable, 56 percent unfavorable.

This is also a group — whites with incomes under $50K — that’s moved away from Romney over the past two weeks, with his unfavorable numbers jumping from 29 to 49 percent (exactly where Gingrich is as well).

Read the full poll results

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