Chris Boedecker defeated Carla Roberts in the GOP primary for state House District 81.
With 13 of 14 precincts counted, Boedecker defeated Roberts by a margin of 71 percent to 29 percent.
Boedecker will face Democratic incumbent Scott Holcomb on Nov. 6 in the general election.
Early in the campaign, Boedecker charged that Roberts was not a legal resident of the district, and therefore should not be allowed to seek the office.
However, the Georgia Office of Administrative Standards rejected the challenge.