Sesame Street was mentioned twice in last Sunday's episode of the Simpsons. In this episode, the town of Springfeild is sick of the pandering made by political candidates, and puts Ralph Wiggum in as a write in Candidate.
one line, a commentator said, "Can Ralph go from Sesame Street to Pensilvania Avenue?"
later on Ralph is in the center of a bidding war between the Republican party and the Democratic party. Someone asks Ralph who he likes, and Ralph replies, "uh...Elmo?"
I forget the rest of the gag, but they make a reference to someone named Elmo in politics, and I just can't remember his name, or I'd give the rest of the joke.