The recent anti-Mitt Romney contagion is spreading beyond South Carolina.

Gallup's tracking poll of the Republican presidential race reported Friday that the GOP front-runner -- whose nomination seemed inevitable as recently as Monday -- has watched his national lead among Republicans erode this week. On Monday, the ex-Bay State governor stood at 37 percent, according to Gallup. At the time, Newt Gingrich had just 14 percent of the vote.

By Friday, Gingrich had cut Romney's edge by more than half. Romney's support had fallen to 30 percent, while Gingrich surged to 20 percent. That's 13-point swing between the two candidates in five days.

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The Gallup poll is evidence Romney's collapse isn't confined to just South Carolina, where surveys show him now trailing Gingrich. A Clemson University 2012 Palmetto Poll released Friday shows the onetime House speaker leading the state at 32 percent, six points above his Massachusetts rival. The forces pulling him down in the Palmetto State have clearly reached across its borders -- something Romney acknowledged as much Friday.

"I expect that Newt will win some primaries and contests, and I expect I will as well," he told conservative talk radio host Laura Ingraham. "My job is to make sure I get the most delegates by the time we're finished -- hopefully, 1,150 or so -- and I have a path to do that. But I'm not expecting win them all."

It's an answer reminiscent of the one Romney used to give before Iowa and New Hampshire, when his status as the race's relatively weak front-runner had him preparing for a long, drawn-out campaign. The chances of a quick knock-out seemed tantalizingly close after the first two nomination contests, which originally appeared to boost him to escape velocity from the rest of the field (hence his rise to 37 percent nationally by Monday). Instead, he's once again falling back to earth.

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