Governor Scott Walker has issued an executive order to set September 1 as a special primary election for the 99th Assembly District. Chris Kapenga represented the district since 2010 and had his last day in the Assembly on August 5. Kapenga defeated Democrat Sherryll Shaddock in a special election for the 33rd Senate District, which covers parts of Waukesha County. Senator Paul Farrow, who was elected as the Waukesha County Executive in April, vacated the seat in July.

Four GOP candidates have filed to run in the heavily Republican district: Cindi Duchow, a small business owner and Town of Delafield Supervisor; Dave Westlake, a small business owner and West Point graduate who ran for the U.S. Senate in 2010; Spencer Zimmerman, a U.S. Air Force Veteran and driver for a limousine service; and Scott Owens of Dousman.

Following the primary election, a general election will be held September 29. As of this writing, no democratic candidates have declared their candidacy.