I know a decent amount of Republicans/Libertarians who think either Stewart or Colbert (do they get the joke?) or Maher are funny. And I think it's because they go for comedy and THEN politics.

Remember that failed Fox News comedy show? They went for politics first, comedy second. For some reason I've gotten that impression from 'conservative' comedians and talk show hosts.

I would also point out the "liberal" comedians are generally not politically correct. Plenty of their stuff can push the lines of various gender/race stereotypes, and be crude and raunchy. Silverman comes to mind, and of course Carlin (who hated both parties but hey, not many atheists are getting invited to CPAC, dead or alive).

And of course there are the two best cartoons for adults, Family Guy and The Simpsons (although the Simpsons peaked a long time ago and I haven't gone out of my way to watch new episodes for many years).