Although today’s Georgia candidates are a better fit for the current Democratic Party, and may more easily energize the young and nonwhite voters who make up its base, they have struggled in much of the state’s rural areas. Mr. Biden was able to defy this trend in his November victory, outperforming Ms. Abrams’s 2018 showing and Mr. Ossoff’s November performance in some of the state’s most conservative redoubts.

“That was enough to win the state by 12,000 votes,” said Michael Thurmond, the chief executive of DeKalb County. “And it shows why we need to do better reaching working-class white voters.” (The president-elect also ran better than Ms. Abrams and Mr. Ossoff in much of metropolitan Atlanta.)

If the Democrats have shifted away from putting forward candidates like the Mr. Miller and former Senator Sam Nunn, another centrist from small-town Georgia, Republicans have turned to elevating candidates much like their national leader: David Perdue and Kelly Loeffler are wealthy business executives with little political experience.