Voters who take to the polls Thursday could be making history. Only one incumbent county commissioner is guaranteed a return to office as DeKalb County looks at what could be a historic turnover in its leadership.Polls open around the county at 8 a.m. and will remain open until 7 p.m. Thursday, Aug. 2 for those who have not taken advantage of the early voting option.At best, if all incumbents who remain in the race win, there will be only six incumbents returning meaning at bare minimum there will be 58 percent turnover on the 14-member council. The Democratic primary and attrition left the sixth district as the only district where there must be at least one incumbent survive as Betty Jean Atnip and Jeff Barnes are running in a three-way race, facing Republican nominee Matt Adcock.