Last night on CNN, after Newt Gingrich’s defeat speech in which he barely suppressed his rage at Romney (whose negative ads destroyed Gingrich’s campaign), David Gergen observed that it sounded like Newt was committing himself henceforth not to victory, but to ruining Romney. Today, David Corn echoes that insight:

In a bitter and spiteful concession speech last night in Iowa—Kanye West could do no worse—the former House speaker, who finished fourth, signaled a shift in his mission. He would no longer be running to obtain the Republican presidential nomination; he would be campaigning to obliterate Mitt Romney. He would be Sherman; the former Massachusetts governor would be Georgia.

If Gingrich does pursue this march—and there are two debates this weekend in New Hampshire in which Gingrich can be a suicide bomber—Gingrich will be reaching the peak of his 30-year career as a Republican demolition man.

Corn says that Romney’s flip-flops give Gingrich plenty of ammunition, but I’m not sure that’s true. Gingrich was a big fat target in Iowa, because he’d never run for the presidency, and his boobery and hypocrisy had never been held up to national scrutiny. Romney ran in 2008, and he’s been running this year for a long time. It’s not news to anybody that Romney is a flip-flopper. And Romney does not have the heavy personal baggage that Gingrich does. True, Romney doesn’t inspire much passion or depth of commitment … but who else is there for Republican voters to go to? It’s hard to believe that people convinced by Gingrichian attacks that Romney’s a dud are all going to break for Gingrich. That may not matter to Gingrich, if his goal is merely to ruin Romney. But I’d bet that most GOP primary voters, though their hearts might tell them Paul or Santorum, are going to shrug and vote for Romney as the candidate most likely to defeat Obama. A bunch of sour Gingrich attacks may stretch the process out and damage Romney for the fall, but don’t forget that lots of people thought the protracted, ugly Obama vs. Clinton contest in the 2008 Democratic primaries would fatally wound Obama in the general election. Didn’t happen.

The thing to keep in mind, though, is that Newt Gingrich has one of the biggest egos in politics, and just two or three weeks ago was saying publicly that the GOP nomination was his. Newt’s all about Newt, and Newt’s not an idiot. He’s potentially a dangerous man to Romney, but at this point, I’m not convinced he’s much more than an ankle-biter.