Start your day off right:

Oakland A's - Bart Simpson - Reliable bad-boy winners who march to the beat of their own drum. Locked in a constant struggle against the overbearing establishment. Every time you think they're going to get what's coming to them, they weasel out of it and surprise you again.

Kansas City Royals - Gil the Salesman - Forever facing in an uphill battle to be competitive. Their failures tend to be more sad than comical. Others are just glad they're not them.

for the rest of the league:
http://barstoolsports.com/article/The_Definitive_MLB__Simpsons_Analogy_List/344/