Gov. Gary Herbert formally appointed Jon Cox to fill the vacancy created in House District 58 when Herbert picked Rep. Spencer Cox as his new lieutenant governor.
"Jon Cox has demonstrated an ability to be a strong and able voice for the people he served in Sanpete County as a commissioner," Herbert said in a statement. "I am confident that in his new legislative role he will continue to advocate for Utah's rural communities."
Jon Cox, a distant cousin of Spencer Cox, had been a Sanpete County commissioner, filling the seat held by Spencer Cox until Spencer Cox was elected to the Utah House in 2012.
Before that, Jon Cox worked for five years as a constituent liaison in Sen. Bob Bennett's office and now is an assistant professor of history at Snow College.
Jon Cox beat two other candidates in a special election among Republican delegates in the district, which covers Sanpete and Juab counties.
He is expected to be sworn in Wednesday, when the Legislature meets in its monthly interim session.