Since republicans tend not to understand any kind of intellectual humor (not that snl can always be said to fit in that category—and I don’t know about Stewart and Colbert since I’ve never seen them), comedians with any brains, by default, end up as democratic supporters.
However, should a democratic administration fuck up, you can be sure that the comedians will be satirizing them mercilessly, too. I can only imagine what the snl impersonators of Obama and Biden will be like. There is much there to make fun of.
The republicans have made a theme of his “slickness.” As if he’s pulling something over on the public. Remember “Slick Willy?” It’s basically a republican ploy to try to turn the brains difference their way. Joe Sixpack, and Joe the Plumber are the same thing. It’s a hamfisted way of trying to get supposedly stupid working americans to mistrust intelligence (they don’t get it) and support republican policies.