Very tough poll.

Kliban's stuff is hard to get into. Most of the time it's either so low-brow that it disgusts me, or it goes right over my head and I just don't get it. I had to go for Larson, because at least I always "get" his cartoons, even if they're not always consistently hilarious.

So the reason it was tough is because it was disgusting/unintelligible vs. not always hilarious? Seems like an easy choice to me.