With all 40 precincts and absentee ballots counted, Mayor Robert Reichert and C. Jack Ellis are headed for a runoff.
Reichert led the field of seven candidates with 17,810 votes giving him 49 percent of the ballots.
A candidate must receive 50 percent plus one vote to avoid a runoff. Reichert was 151 votes short of avoiding a runoff.
Ellis, with 30 percent of the vote, took 10,838 ballots.
Ellis sounded conciliatory early in the evening when Reichert gained an early lead.
After learning that Reichert didn't win outright, Ellis said, laughing: "I unconcede."
"I'm going to lace up my boots in the morning and go out ... we are going to win this race," Ellis added.
Reichert said he also is going to start his runoff campaign early Wednesday morning.
"First thing tomorrow, we're going to call all the candidates and ask for their endorsements," he said. "We're going to make the run off a unifying event to make me mayor."
Bibb County Commission Chairman Sam Hart came in third with 2,774 votes and 11 percent.
Charlie Bishop, a former county chairman, had 2,452 votes, 7 percent.
Joe Allen had 613 votes, 2 percent.
David Cousino had 107 votes, 1 percent.
Anthony Harris ran as a write-in candidate, but the board of elections did not report any write-ins for him Tuesday.