When Homer says to Moe "I used to hate the smell of your feet. Now it is the smell of victory", he is quoting a line from Apocalypse Now.
After Lisa chooses who she thinks she is going to win, she states that she will bet her entire college fund on it. Homer then calls Moe to place his bet and tells him to put $23 on New York (though "Lisa's First Word" revealed that Homer put Lisa's college fund in with Lincoln Savings and Loan, which was infamously shut down in 1989. The $23 could be all that was left of it).
Ugolin and Cesar appear for the first time sinceThe Crepes of Wrath, only now, they are out of prison, living near Paris (we can see The Eiffel Tower by the window), and watching Jerry Lewis movies in an apartment.
Lisa says she and Homer used to have burping contests, possibly a callback to how in the Tracey Ullman Shorts she did burping contests with Bart.