ATLANTA — An Atlanta councilwoman could become the city's first white mayor in a generation, facing off against a black state senator in a runoff next month.

With 100 percent of the precincts reporting early Wednesday, Mary Norwood received 45 percent of the vote, compared to Sen. Kasim Reed at 38 percent. City Council president Lisa Borders was a distant third with 14 percent and conceded early.

Norwood did not get 50 percent of the vote plus one to avoid a runoff. Election officials estimated voter turnout could be at its lowest in recent memory, with far fewer ballots cast than the 35 percent of registered voters who participated in recent mayoral races.

Norwood, Reed and Borders were the front-runners in the crowded field for much of the campaign and battled for weeks over public safety and open government, as the issue of race loomed over the contest. Political observers say the race will continue to polarize voters along racial lines in the weeks before an anticipated Dec. 1 runoff.

Borders thanked supporters at her Election Night headquarters downtown.

"I am conceding the race," Borders said about three hours after the polls close. "I'm not going to talk about endorsements tonight."

Norwood sounded upbeat.

"I am really focused on this city and our citizens and the issues that matter to our citizens," Norwood said. "So I have been totally focused on winning this campaign tonight or 27 days from now. This has been a totally unified, united campaign across the city and that's what I have wanted and that's what it is."

Reed, whose momentum has swelled in recent weeks, told cheering supporters he was "ready to go for this city."

"I will fight for you," Reed told the crowd. "I will stand up for you and we will make Atlanta the city on a hill again."

Atlanta has had a long line of black mayors since 1973. Current Mayor Shirley Franklin, the city's first female in the office, was barred from seeking a third term.