David Frum: “It’s striking that almost none of Gingrich’s former colleagues in the House has endorsed him for president. Striking that nobody associated with a past Republican presidential association has done so. He is a candidate of talk-show hosts and local activists — and of course of Rick Perry and Sarah Palin — but not of those who know him best and have worked with him most closely. Gingrich may raise more money after his South Carolina win. But prediction: Romney will raise even more, among the great national network of Republicans who recognize that to nominate Gingrich is to commit party suicide.”

Jon Meacham: “The analogous elements are obvious. Like Nixon, Gingrich is smart, with a wide-ranging and entrepreneurial mind. Like Nixon, Gingrich is a striver who seems insecure around traditional establishment figures even though he has achieved much more than nearly all of the politicians, editors and reporters he seems to at once loathe and fear. Like Nixon, Gingrich is fluent in the vernacular of cultural populism, brilliantly casting contemporary American life in terms of an overarching conflict between ‘real’ people and distant ‘elites’ bent on the destruction of all that is good and noble about the United States.”

“At the moment, that record is held by the 2000 New York Senate race between Hillary Clinton and Rep. Rick Lazio (R). The two candidates raised and spent a combined $70 million in that contest — about $40 million by Lazio and $30 million by Clinton,” Aaron Blake reports.

“With Brown and Warren approaching $25 million raised at the end of 2011, they would need to raise and spend another $45 million in 2012 to break the record. Given the quickening pace of donations, that looks likely.”

A new Public Policy Polling survey in Florida shows Newt Gingrich leading Mitt Romney by five points in the GOP presidential race, 38% to 33%, followed by Rick Santorum at 13% and Ron Paul at 10%.

Key findings: “Gingrich has gained 12 points since a PPP poll conducted in Florida a week ago. Romney has dropped 8 points. Paul and Santorum have pretty much remained in place. Their favorability numbers show similar trendlines. Gingrich’s has increased 8 points from +15 (51/36) to +23 (57/34). Meanwhile Romney’s has declined 13 points from +44 (68/24) to +31 (61/30).”

If you missed it, the Daily Beast has video clips of the best moments of tonight’s GOP presidential debate.

Ron Fournier: “Somebody must have awakened the cool-and-nonchalant Romney out of his debate slumber and told him the GOP nomination was slipping away. Gingrich stunned the political world — and frightened much of the GOP establishment — with a landslide victory in South Carolina on Saturday night that erased Romney’s lead in national and Florida polls.”

Andrew Sullivan: “What a different Gingrich tonight: eager to thank and support his rivals; humble with respect to the huge challenges ahead. He has decided to cut the fireworks to foil his critics. And I presume his Super PAC will meanwhile open up various cans of whup-ass on Romney. So this is Newt on his best behavior. Even when Romney called him a ‘disgrace’ three times. Maybe Gingrich is trying to reassure the establishment that he is not the constant bomb-thrower and surprise agent. Maybe he realizes he needs to look more presidential. My own take is that this gambit cannot work for Newt. He is not a serene statesman. He’s a ferocious demagogue. That’s all he knows. I don’t find the new Newt very appealing. But maybe tactically, it makes sense.”

Howard Kurtz: “Mitt Romney was so anxious to attack Newt Gingrich in Monday’s NBC debate that it was as though he was delivering a PowerPoint presentation on speed.”

David Brody: “Romney was very much on the offensive tonight as he landed subtle punch after punch on Gingrich’s record of leadership and attempting to paint him as a Washington insider. It’s a smart play by Romney and a strategy that he must implore. If Romney can paint Gingrich as your typical influence peddling same old politician then voters will be turned off and Romney will probably see himself on top again very soon. So this is an important battle. The problem for Romney is that Gingrich has SO FAR been able to masterfully turn his insider image into this outsider man of the people.”

Tim Alberta: “Like a stand-up comedian whose routine suffers without echoes of laughter egging him on, Newt Gingrich appeared to be a candidate without cadence Monday night when he found himself searching hopelessly for the secret weapons that have proven crucial to his season of strong debate performances: moderators to scold and audience members to energize.”

With a crucial debate tonight and another one on Thursday, the New York Times reports Mitt Romney has recruited Brett O’Donnell, who served as one of Michele Bachmann’s top strategists during her short-lived presidential campaign, as his new  debate coach.

“O’Donnell is a veteran of presidential debates, having served as a top debate coach to Senator John McCain of Arizona during the 2008 campaign. In that role, he helped prepare Mr. McCain for debates against Mr. Romney and brings those insights to the current sessions.”

Newt Gingrich’s former consulting company will release his contracts with Freddie Mac this evening before the GOP debate, NBC News reports.

Gingrich was reportedly paid $1.6 million under the contracts and Romney had made disclosure of the contracts a major issue in the last day.

Jonah Goldberg: “As I’ve been writing for a very long time, Romney has an authentic inauthenticity problem. In other words, he seems like he’s faking things even when he’s not. He may take positions he doesn’t hold in his heart, but all politicians do that. The problem is that the vast majority of the time he’s no more passionate or convincing about the positions he almost surely does hold in his heart.”

“More to the point, fair doesn’t have anything to do with it. Politics is about persuasion and he’s simply not persuasive. I’m rapidly losing confidence that as a general election candidate he would be able to win over the crucial voters he would need to seal the deal.”

A Wall Street Journal editorial tries to settle down Republicans after Newt Gingrich’s trouncing of Mitt Romney in South Carolina:

“As for the GOP establishment, such as it still is, Mr. Gingrich’s re-emergence is likely to cause a panic attack. They don’t believe he is electable. Our advice would be to relax and let the voters decide. If Mr. Romney can’t marshal the wit and nerve to defeat the speaker, then he isn’t likely to defeat Mr. Obama.”

Mark Halperin: “It seems the Republican Establishment is waiting until after Florida for any panic, hoping Romney can set the universe back in order then. Of course, it will be (even) harder to stop Newt if he wins Florida.”

The latest Gallup daily tracking poll shows Mitt Romney’s once formidable national lead over his Republican presidential rivals has completely collapsed. Romney now barely edges Newt Gingrich, 29% to 28%. They are followed by Ron Paul at 13% and Rick Santorum at 11%.

More potential bad news for Romney: The tracking survey is a five day rolling average and reflects just one day of polling since Gingrich’s blow out primary victory in South Carolina.

Sen. Scott Brown (R-MA) and his likely Democratic challenger Elizabeth
Warren have reached a deal to keep super PACs out of their race, reports
The Hill,
marking “the first attempt by candidates to wrest control of their
races back from groups over whom they have no direct control.”

“The
pact signed by Warren and Brown on Monday imposes a financial penalty
whenever an outside group intrudes on the race. If an outside group
places a television or Internet ad supporting a candidate, the candidate
would be required to donate 50 percent of the cost of the ad to a
charity of the opponent’s choosing within three days. Negative attack
ads would also trigger the penalty, with the candidate whose rival is
attacked being forced to forfeit half the cost.”

Meanwhile, Greg Sargent notes Karl Rove’s Super PAC already appears to be signaling that it may not honor the deal.

“We could see an October surprise once a day from Newt Gingrich.”

— Mitt Romney, quoted by Slate, on what might happen if Newt Gingrich wins the GOP nomination.

Michael Crowley: “To the extent Newt threatens the Establishment, it’s because of his electability-or lack thereof. The GOP’s mandarins see Gingrich’s nomination as a sure way to blow their chance of deposing Barack Obama. They see Gingrich as the political equivalent of a Fukushima nuclear plant worker, with polls showing him to be lethally irradiated by his negative approval ratings. Whereas Mitt Romney is running about even with Barack Obama in head-to-head polling, Newt loses by double-digit margins. Sure, those numbers could change if Gingrich beats Romney and wins the nomination, with all the accolades it entails. On the other hand, his grandiosity syndrome may kick in, as it has before, and render him a laughing stock. Hence the many Establishment Republicans now saying things like, ‘Newt means losing 45 states.'”

First Read: “When the remaining four presidential candidates gather for the 18th debate of the cycle tonight in Tampa, FL, the stakes couldn’t be any higher, especially for Mitt Romney and Newt Gingrich. For Romney — fresh off his double-digit defeat in South Carolina and after uneven performances in his last two debates — tonight’s debate is a crucial moment for his campaign. Either he rises to the occasion (by providing sharper answers, by disqualifying Gingrich, and by proving to GOP voters the confidence he can be their guy in November), or he struggles again, giving Gingrich a path to overtake him in Florida. For Gingrich, tonight’s debate will prove if he can withstand the attacks (because they’re coming), and if he can pull off another strong performance.”

“And don’t lose sight of Rick Santorum (who has leveled pointed criticism
at both Romney and Gingrich in past debates) or Ron Paul (who has
sometimes has served as Romney’s wingman). If we learned anything from
South Carolina, it’s that the debates have mattered, and tonight’s
debate likely won’t be any different.”

The debate starts at 9 p.m. ET on NBC.