One thing you have to admire about David Letterman: if people get angry with him for doing a bunch of fat jokes, he is guaranteed to keep doing fat jokes. We all have guns we need to stick to, and making fun of Chris Christie's weight is one of Dave's.
Presenting yet another Christie-inspired Top Ten list on Wednesday's show, Dave showed some restraint by having only seven out of ten jokes be of the "fat guy" variety. What was particularly notable about it is how much the truly barbed jokes stood out because of their proximity to the more infantile gags.
Clearly, the answer to the question of why Christie chose Romney is simple: Who else could he possibly throw his weight behind?