Twenty-four-year-old Colton Moore defeated veteran House District 1 Rep. John Deffenbaugh in voting on Tuesday.
The University of Georgia graduate won with 54 percent of the vote.
The final tally was Moore 2,184 to 1,858 for Deffenbaugh, of Lookout Mountain.
In Catoosa County, Chuck Harris received eight more votes than incumbent Robert "Bobby" Winters for the County Commission, District 2, seat. It was 458 to 450.
Another incumbent, Ray Johnson in District 4, was behind Charlie Stevens 623 to 543.
In a Catoosa County School Board contest, incumbent David Moeller outpolled Brad Hayen 755 to 626 in District 4.
Catoosa County voters approved the SPLOST sales tax 3,049 to 1,796.