Rick Perry, Mitt Romney internals show Newt Gingrich slippage, sources say

A weeklong blitz of negative ads from Ron Paul and "Restore Our Future," the pro-Mitt Romney super PAC, have taken a toll on Newt Gingrich's standing in Iowa, internal numbers from the Rick Perry and Romney camps show, according to multiple sources.

Sources didn't provide specific numbers on how far he's slipped, but it's perceptible in both camps' numbers, the sources said.

Perry has been inching up, the sources said - in part thanks to his faith-based push but largely because of his controversial anti-gay rights ad, and the big question is whether he draws at all from Romney and pushes him down out of the top three finishers in the state.

The person who is holding strong, according to the internal numbers, is Paul, who has a true shot of winning the caucuses, according to several Iowa Republican insiders surveying ground games and energy.

"Gingrich [is] leveling off and the attacks are starting to permeate the minds of Iowa caucus-goers," said one veteran Republican caucus-watcher in Iowa. "[The] level of attention being played to the caucuses by Iowans is still high, despite the holidays. That's uncommon. I believe Paul can trip up Newt here, and that's great news for Romney because Newt is done if that happens. Watch Rick Perry. He's going for a top three finish, and that could be to Romney's expense."

If Romney were to come in fourth, that would be awfully hard to recover from, given potential spillover in New Hampshire. And if Paul were to finish first, many Iowa GOPers believe that would be hard for the Hawkeye State to recover from in terms of maintaining premiere status in the nominating process.