Republican presidential candidate, former House Speaker Newt Gingrich and former Massachusetts Gov. Mitt Romney participate in a presidential debate at St. Anselm College in Manchester, NH, June 13, 2011 (AP Photo/Jim Cole, File).

On the night of Newt Gingrich’s victory in the South Carolina primary, Republican strategist Steve Schmidt predicted on MSNBC that the GOP establishment would “panic” if Gingrich won Florida. They didn’t wait that long. As soon as Gingrich’s bounce from South Carolina briefly brought him to the top of the polls in Florida, the Romney campaign and the Republican establishment amplified their attacks on Gingrich.

The Romney campaign holds daily press calls criticizing Gingrich. In addition to the lower-profile surrogates such as Senator Jim Talent (R-MO) and former Representative Susan Molinari (R-NY), they’ve started dispatching some heavy hitters. Last week Senator John McCain held a call complaining that Gingrich was a profligate pork-barrel spender.

Many in the conservative media, in collaboration with current and former government officials, have been digging into Gingrich’s congressional tenure. National Review, which endorsed Romney in 2008 and has already editorialized against Gingrich’s candidacy in this cycle, has spearheaded the campaign. Last week it ran another editorial against Gingrich. NR’s editors did not bother pretending that their concerns about Gingrich revolve around some phony issue like pork-barrel spending, a fixation for conservative purists who seem not to care that the military budget they refuse to cut is roughly 100 times as expensive. They cut right to the core of what bothers establishment Republicans about Gingrich: the fact that he is an incredibly weak candidate in the general election. “Amid all the tumult of the last 18 years there has been this constant: Gingrich has never been popular,” they wrote. “Polls have never shown more than 43 percent of the public viewing him favorably at any point in his career.”

Meanwhile NR’s Jim Geraghty exhumed a story of Gingrich’s strong-arm tactics from his tenure as Speaker. According to Geraghty, Senator Tom Coburn’s (R-OK) memoir of his tenure in the House of Representatives under Gingrich “paints a picture of Gingrich as a raging egomaniac, wildly hypocritical and quick to toss Class of 1994 principles.”

National Review’s most significant blow to Gingrich last week surely came in the form of an article by Elliot Abrams. Abrams is the epitome of a neoconservative Republican insider: son-in-law to Commentary’s Norman Podhoretz and Midge Decter, Abrams served in President Reagan’s State Department and on George W. Bush’s National Security Council. Abrams recalls with tremendous bitterness that during the 1980s, Gingrich was frequently critical of Reagan’s foreign policy. And in typical Gingrich fashion, he used wildly over-heated rhetoric to make his argument. Abrams depicts Gingrich as a hostile critic of Reagan’s policies that supposedly slayed the Soviet Union. This cuts directly into the central argument of Gingrich’s candidacy, that he is the “Reagan conservative” who worked with Reagan and will replicate Reagan’s successes.

National Review’s second-biggest score against Gingrich was a scathing statement former Senate majority leader and 1996 Republican nominee Bob Dole provided them. “If Gingrich is the nominee it will have an adverse impact on Republican candidates running for county, state, and federal offices,” wrote Dole. “Hardly anyone who served with Newt in Congress has endorsed him and that fact speaks for itself.”

Even Tom DeLay, a former deputy to Gingrich in Congress, told a radio show that Gingrich is “erratic, undisciplined.”

As Politico reported, these attacks reverberated widely in the conservative echo chamber. The Drudge Report linked prominently to anti-Gingrich items such as the Abrams piece.

Other prominent conservatives and Republicans came out against Gingrich: The American Spectator’s founder, Emmett Tyrrell, compared Gingrich to Bill Clinton in a widely reprinted column. (That’s a serious insult coming from Tyrrell since his magazine was behind many of the smears and conspiracy theories about Clinton.)

More insurgent-friendly conservatives have tried to push back on Gingrich’s behalf. The Daily Caller’s Matt Lewis posted a video of Nancy Reagan saying, “Barry Goldwater handed the torch to Ronnie, and in turn Ronnie turned that torch over to Newt.” In a Republican primary that’s like being anointed by Saint Mary herself.  Gingrich’s campaign blasted the video out and Gingrich then mentioned the event at a debate as a fond recollection, although he had clearly forgotten about it until recently. The American Spectator ran an article pointing out that, however tenuous Gingrich’s ties to Reagan, they were obviously stronger than those of Romney, who insisted in 1994, “I was an independent during the time of Reagan/Bush. I’m not trying to return to Reagan/Bush.”

The biggest boost to Gingrich may have come Friday evening when Herman Cain endorsed him. Even though the accusations of long-term adultery and serial sexual harassment—along with Cain’s embarrassing feeble grasp of important policy issues—derailed Cain’s candidacy, he remains a popular figure on the right. Many times on the campaign trail I interviewed former Cain supporters who said they were having trouble choosing a new candidate and they would vote for Cain if he got back in the race.

Even so, the onslaught of establishment criticisms and negative ads from Romney’s campaign and his Super PAC seemed to have succeeded in reversing Gingrich’s momentum. Recent polls show Romney headed for a double-digit victory in Florida. Unlike revelations of his past infidelity in mainstream news outlets, Gingrich cannot turn these criticisms to his advantage by attacking the media. The result, as we saw in Thursday’s debate in Jacksonville, was Gingrich’s being hoisted by his own petard on everything from his relationship with Freddie Mac to his attacks on Romney’s wealth to his past support for an individual mandate in health insurance.

The question going forward will be whether Romney and his establishment backers have Gingrich down or out. Gingrich has come back from the dead twice before in just the last two months. Maybe he can again.