He's just fighting the what I call the Patriot Fight at this point, He stated flat out after South Carolina he knows he isn't going to be president, and hinted as much much earlier.
His goal is simply to take the delegates he can garner to Tampa and squeeze the party for a plank or two in the platform, hoping that Romney may not get the delegates for a first ballot nomination, so that his delegate power, though small, can make a diff before releasing them.
I'd imagine in his heart of hearts he knows at his age this is probably the last roundup for which he can get this degree of media attention for the policies he advocates. One can see it as futile Don Quixote syndrome, or simply a man toward the end of his significant public influence going out on principle for whatever difference he might make to the public conscience, for a country he truly loves.
I tend to see it as the latter and he probably does too.
- OS
edit: Oh, and Newt, he's just a megalomaniac; he can't help it. I suppose he has convinced himself in some extended sense of similar altruistic politics, but he's just fooling himself, the real impetus is all about Newt. He and Obama share that. They both see themselves as Grand Historical Figures, the smartest guys in any room.