So Newt Gingrich, fresh off a 5th place finish in Iowa and a (barely) 4th place finish in New Hampshire, now goes to South Carolina guns blazing. He's targeting Mitt Romney, but if he really wanted to beat Romney he presumably would just drop out and endorse Rick Santorum (or I suppose Rick Perry). Instead, he's choosing a course that perhaps makes it more likely that Romney will win, but that (at least in the margins) weakens him in November, which also means that he's seriously annoying GOP partisans.
So what is Newt thinking? I went through this last week with Rick Perry. Matt Glassman stresses that candidates may be acting strategically, but with goals other than winning the nomination. I mostly discounted that with Perry, but Newt? That's a whole 'nother story. There have been two basic Theories Of Newt during the 2012 cycle. The first is that it's just a brand-maintenance exercise, with the strongest version of that claiming that Newt actively doesn't want the nomination; he just wants to make money. The other is that Newt is following his visions of himself as Churchill or de Gaulle, about to be called back from political exile to save his nation at it's moment of greatest peril; if that's the case, Newt is really demeaning himself in his own eyes by even participating in the process at all.
What I can't see is how his present course of action fits with either of those goals. Surely getting beat up by Rush Limbaugh can't be good for his standing within the conservative marketplace. But it's also not good for getting the nomination! Unless this is all some elaborate plan to alienate Newt from his party, thus making him even more Churchill-like when they finally wise up and beg him to be their nominee at some unspecified point in the future (this summer? In 2016? After an EMP attack by the Iranians and the North Koreans next March?)
Or maybe, as some have said, it's just blind rage revenge against Mitt Romney, even if by staying in he's actually helping Mitt. After all, Newt is a great snake oil salesman, but not a particularly good strategist, whatever he constantly says about himself.