Dennis Thornock won the Republican primary for Custer County Commissioner District 2 with more than 80 percent of the vote, defeating former county prosecutor Justin Oleson, whose disbarment last year shadowed the race.

Bingham County Coroner Jimmy Roberts lost his Republican primary to political newcomer Scott O. Tweedy by a 74-to-26 margin Tuesday, while incumbent Assessor Donovan Harrington defeated his challenger to retain his seat.

Madison County Commissioner Dustin Parkinson held his District 2 seat by 34 votes in a three-way Republican primary Tuesday, while uncontested District 1 incumbent Brent Mendenhall coasted to renomination.