Yosemite Sam is running for mayor of a small town, declaring such empty promises as: "There's enough fresh air and sunshine in this great country of ours for everybody- and I'll see to it, that you'll get your share!". Bugs Bunny is underneath the podium drinking carrot juice when Sam makes a pledge to make good on his previous promise "to rid this country of every last rabbit" if elected. Bugs then decides he needs to fight against Sam by running against him for mayor.
Bugs proceeds to quickly try and win the townspeople over (including referencingTheodore Roosevelt's famous "I speak softly, but I carry a BIG stick!" quote). However, Sam declares that he speaks LOUUUUUD and carries "a BIGGER stick, and I use it too!" (When watching this on The Bugs Bunny Show, Daffy Duck says "I speak medium, and I carry the BIGGEST stick.) Sam has more than a few tricks up his sleeve. He steals Bugs' cigar stand, to which Bugs switches his "SMELLO" cigars with five-cent ATOM Explosive Cigars ("You Will Get A BANG Out of This"). He sends a boxful of "assorted" picnic ants to steal all of the food at Bugs' picnic, to which Bugs hides a dynamite stick in a watermelon for him. Then he rigs a cannon at the front door of Bugs' headquarters and greets Bugs with friendship at the back door, but the plan backfires on him when Bugs pretends that a pretty girl named Emma who loves Sam is at the front door. Then he challenges Bugs, asking him if he can "play the pi-anna", and Bugs takes the challenge, so he rigs explosives in the piano at a certain key and presents the piano to Bugs to play "Those Endearing Young Charms" (a gag recycled from a Private Snafushort), but Bugs misplays the tune on purpose to infuriate Sam, who plays it correctly and falls for his own trap.
A quick chase through the streets leads the pair to the parade for the newly elected mayor, a literal "dark horse" candidate — a chestnut-colored mare, whose car bears a sign reading "Our New Mare". Oddly, Bugs suggests a game of Russian Roulette and hands Sam a gun. Sam agrees, points the gun at his head, closes his eyes and pulls the trigger, and gets the click of an empty barrel. He then hands the gun to Bugs, who points the gun to his head, closes his eyes, and pulls the trigger as the "camera" irises into black in the center of the screen to the sound of a gunshot. An iris opens up on Bugs to the left, having ducked and holding a smoking gun as he proclaims "I missed!". The right side of the screen irises open to reveal a scorched, hatless Sam shot in the head by Bugs' wayward blast, and Sam says: "I hate that rabbit!" (see "Censorship" note below for more information about the ending).