Alex Massie explains the main theme of the Gingrich campaign:

And what is Gingrich’s campaign actually about? Apart from typically loopy notions such as colonising the moon, nothing more than a declaration of independence from a contemptuous (and contemptible) liberal media and an anti-American elite that’s notionally happy to embrace American decline. It is a brand of politics that bathes in the warm, comforting waters of victimhood but that has nothing useful to say about the actual challenges the United States faces.

It is fitting that the supposed “ideas” candidate in the party that likes to flatter itself as the “party of ideas” doesn’t actually have any that aren’t risible or impossible. What’s striking about Gingrich is that his debate performances, interviews, and speeches are typically filled with contempt, as if he is always saying, “Can you believe that I have to live on the same planet with these people?” One of Gingrich’s political weaknesses is that he cannot help but be contemptuous of his opponents. He doesn’t seem to know any other way to respond to criticism or disagreement. That has kept his candidacy afloat for a time, and it has helped him to recover from two earlier collapses in this campaign, but in the end it grates on almost everyone and makes them into opponents as well.

Consider Gingrich’s duel with Romney over immigration issues. Gingrich thinks he sees an advantage in being to Romney’s left on immigration, because he thinks Romney is vulnerable with Latino voters in Florida on this issue, and they represent an opportunity for Gingrich to prevail there. What does he do? He doesn’t make an argument for his preferred policy, and he doesn’t simply criticize Romney’s policy as mistaken. He bashes an immigration position that he previously advocated as a “fantasy” that only someone in “the world of Swiss bank accounts” could endorse. Presumably, the “world of Swiss bank accounts” is the next world that Gingrich intends to turn into an American state.

It isn’t just that he is abandoning a previously-held position, but that he is willing to excoriate anyone who still holds it as oblivious to reality. It is never enough for Gingrich that his opponent is wrong. The opponent must also be wildly, irresponsibly, unspeakably foolish and out of touch. Since Gingrich engages in overkill like this for every one of his tactical maneuvers, his enemies multiply quickly, and his unfavorability rating continues to climb. The manner of Gingrich’s temporary revival over the last two weeks is the reason why his candidacy will not be able to compete effectively in the coming weeks and months.