Chief Magistrate Judge Martin Valbuena defeated challenger Dan Collins by eight votes out of more than 5,900 votes cast.
District 31 State Sen. Bill Heath, R-Bremen, defeated challenger Bill Carruth 55 percent to 45 percent in the race for Heath's Senate seat.
Carruth, a former Paulding County Commission chairman, won Heath's home county of Haralson but lost in both Paulding and Polk counties. Heath received 6,330 votes to Carruth's 5,259 votes.
Former representative Bob Snelling easily won the Republican nomination for the new House District 66, which include Douglas and Paulding counties.
Snelling won 82 percent of the vote in defeating Mike Miller, a Douglas County School Board member.
Snelling will now face Democrat Kimberly Alexander of Dallas in the Nov. 6 general election for the House seat. He previously served in the state House from 1994 to 2002.