Some of the photoshopped images of Krusty feature him as: Neil Armstrong, the soldiers at Iwo Jima, the Tank Man, and Jim Leavelle, the Dallas police detective escorting Lee Harvey Oswald through the basement of the Dallas police department when Oswald was shot and killed.
Mayor Quimby's quip about his regretting building his lover an opera house after hearing her voice for the first time was a reference to Citizen Kane in Rosebud, specifically his making a similar mistake.
In Krusty's campaign commercial, the voiceover saying "The man from funny" is a parody of an ad for Bill Clinton in 1992, where Clinton was a the man "From a town called Hope."
When the plane hit the living room of the Simpsons' house, it reversed by itself. Planes cannot reverse by themselves. They will need a pushback car or must turn around.
When Krusty says he's on Pepto and Xanex, Marge's pearls and Lisa's dress turn to a light orange.
Planes can't fly so low.
Marge says the family haven't had a decent night's sleep in weeks, however flights aren't allowed to operate between certain times (night).
Krusty's navel can be seen when wearing the tank-top in his offensive sketch.
Krusty is shown to be with the Simpson family in a hotel room on the night of the election. Most political candidates, especially those running for a seat in the United States Congress, typically hold rallies on election night, where the candidate gives a victory or concession speech (depending on the outcome) to a room full of supporters