I think this assessment of Newt Gingrich by Jeffrey Goldberg, talking to Hugh Hewitt, is accurate:

HH: Yeah, I’ve had it since I was 40. It doesn’t work for me. But would [Newt] be a plausible candidate? This is what I wanted to come to, Jeffrey Goldberg. He sits down with the New Yorker reporter, he rips everybody in the Republican party, and he drives away from the scene of the car crash humming. I mean, that is not a presidential campaign.
JG: It’s an unusual presidential campaign. I think, I mean, look, one of the reasons reporters like him is that he’s interesting and speaks his mind, and has, is this fountain of ideas, and as the joke goes, some are good and some are bad. I don’t understand how you get from the point he’s at right now to a plausible candidate for president. I think he’s hoping that it’s the power of his ideas, and the power of his insurrection, if you will, catapults him to the top, and keep in mind something about Gingrich. It’s very interesting, and it’s very unlike even some of the main Republican, Democratic candidates. It’s every time he opens his mouth, people pay attention.