I actually do think Chris Christine is too porcine to be elected president. I know he said otherwise, pointing in part to the fact that he'd been elected governor.
But there's a big difference between governor and president. Outside of the what, 15 or so percent of the population that really follows politics, no one cares who their governor is. But nearly everyone cares who their president is. Even if you pay much attention to politics, you see and hear the president every day, and you want someone in there who at the very least doesn't annoy or embarrass you, someone you can bear hearing and seeing for four interminable years.
Christie has a bit of luck reposing in the fact that that his face doesn't look quite as bloated as his midsection does. If you see a head shot of him you think well, he's chubby, but no more. Then you get a gander at the full monty, as it were, and he looks like someone inflated him from the sternum down. He is similar to Mike Huckabee in this respect, although Huckabee is even less jowly.
Fairly or not, many people see that kind of amplitude of girth as a sign of irresponsibility or lack of discipline or something. Now, he's exactly the kind of "I yam who I yam" sort who'd run tipping the scales at 25 stone or whatever he is, and that would buy him a certain kind of admiring press for a while, but the public wouldn't accept such a person as president. And anyway, as Gingrich said last week, being right about something for the first time in 20 years, none of them can beat Hillary.