Pima County prosecutors say 43-year-old Daniel Brito pleaded guilty last month to aggravated assault on an incapacitated victim and theft by control.
Court documents show the victim was wearing a red "Make America Great Again" hat and carrying a "vote Republican" sign days before the November 2018 election when he passed Brito on a street.
The Arizona Daily Star reports Brito tried to snatch the man's hat from behind and started a fight.
Tucson police say the Trump supporter suffered a broken ankle and Brito also punched the injured man multiple times in the head.
Witnesses prevented Brito from leaving before police arrived.
Information from: Arizona Daily Star, http://www.tucson.com