Frustrated with the local government, Marge decides to run for mayor, and to win public support, she begins making Homer the butt of her jokes.
- Back for the Dead: Sebastian Cobb, the scientist who helped Marge back in "Marge vs. the Monorail", returns saying that "I Warned You about keeping that monorail!" gag before being run over by said derelict monorail.
- Call-Back: The episode starts with Mayor Quimby trying to turn the monorail tracks into something useful for the town.
- Evil Cannot Comprehend Good: When Marge tells Homer her position as Mayor of Springfield doesn't place them above the law, he assumes she's saying it because her office is bugged.
- Evil Is Petty: The constant humiliation that has Marge in danger of being impeached started by Helen Lovejoy calling her useless in a town hall meeting... becuse someone (revealed instantly to be her in an inner monologue of her husband Tim) brought a lousy cake to a cake sale and she's putting the blame on Marge.
- Honor Before Reason: Marge decides to stop mocking Homer and instantly gets impeached, leaving the town back in the hands of a dangerous jerk like Quimby. Not that there was much "reason" anyway — the danger of being impeached was dangling over her head thanks to Helen Lovejoy and a very fickle audience anyway.
- Kick the Dog:
- In case you don't like the Monorail (and Quimby's stupidity as a result), its runaway rampage ends by flattening a statue of Leonard Nimoy (which was dedicated to his role helping in the first monorail crisis, ironically). Quimby also spends his whole time deflecting Marge's questions afterwards by being a sexist jerk.
- Helen Lovejoy calls for Marge's impeachment because of a lousy cake sale that is her fault.
- Never Recycle a Building: The events of the episode happen because of an aversion: the creation of a skywalk complete with gardens and an amusement park on the abandoned rails of the Springfield Monorail. The drama that then ensues is because nobody thought of getting rid of the train.
- Nominal Importance: Two Mayoral candidates make a brief appearance before it's announced they didn't get enough votes at surveys to qualify for the debate. Their names aren't revealed to the viewers.
- Shout-Out: The title is an allusion to folk song "The Old Gray Mare".
- Small Role, Big Impact: If not for the man who prevented Marge from fulfilling her promise regarding the Springfield Fire Tire, she wouldn't need to humiliate Homer to retain public support.
- Status Quo Is God: After Marge stops mocking Homer, she's impeached and Quimby regains his position as Mayor of Springfield.
- The World's Expert on Getting Killed: Sebastian Cobb, the scientist who helped with the chaos of the original runaway Springfield monorail, reappears for a few seconds yelling that he warned about keeping the damn thing unscrapped before being run over by the runaway monorail and killed.