Since you said cartoon and not comics, I'll have to ditch my Calvin reply. Instead, I'll go with my old favorite of Bugs Bunny.
Of course, Family Guy is an awesome show and I love Stewie... but for favorite cartoon character, I'd have to go with Jessica Rabbit. Or Tweety Bird, hah!
Spongebob or Patrick. Stewie Griffin or Peter Griffin. Homer Simpson. So many great cartoon characters
I'm with you, hard to stop at just one. 2 that WON'T be making my list: Popeye and anything Flintstone related
Call me old fashion, but I still enjoy those cartoon characters from Marvel. Batman, superman, the flash, x-men, justice league, etc etc.
Of course President Peter Griffin of Petoria My Favorite Phrase "Oh yeah? Well, according to paragraph 7, sentence 3, word 8 of the Geneva Convention..."THE". So, tough luck, Swanson."