MADISON, WI (WTAQ) - Governor Scott Walker called a special election Tuesday for a state Senate seat that’s been vacant for a month-and-a-half.

Republican Rich Zipperer of Pewaukee resigned from the Senate to become the governor’s deputy chief of staff in early August.

Walker scheduled a special election for December 4th – the earliest it could be held at the time Zipperer changed jobs.

A Republican primary is expected, and it will take place on November 6th – the same day as the county, state, and federal contests.

Republicans have held Zipperer’s former Senate seat for years, and two GOP Assembly members earlier announced plans to run for the open post – Paul Farrow of Pewaukee and Chris Kapenga of Delafield.