I don’t watch South Park anymore, but I do recall reading about an episode (I can’t remember which one) that presented Bush in a somewhat favorable light.
So some liberal reporter asked the show’s creators about it: Don’t you know that that episode made Bush look good? (Like it was some sort of mistake.) The creators replied that making Bush look good was their intention.
I loved the episode where the homeless were wandering around begging for “Change” so Cartman led them to California with promises of free stuff.
http://southpark.cc.com/clips/104429/look-glenn-were-saved