Former president Jimmy Carter speaks as Democratic gubernatorial candidate Stacey Abrams listens during a news conference to announce her rural health-care plan in Plains, Ga., on Sept. 18. (John Bazemore/AP)

Georgia Democratic gubernatorial nominee Stacey Abrams’s campaign is calling attention to a letter in which former president Jimmy Carter urged Abrams’s Republican opponent, Brian Kemp, to resign as Georgia’s secretary of state, arguing that “public confidence is threatened” by Kemp’s dual role as candidate and overseer of the state’s elections.

Carter, who still lives in his Georgia hometown with his wife, Rosalynn, sent the letter to Kemp last week.

Kemp’s role as candidate and secretary of state “runs counter to the most fundamental principle of democratic elections — that the electoral process be managed by an independent and impartial election authority,” Carter said in the letter.

“To foster voter confidence in the upcoming election, which will be especially important if the race ends up very close, I urge you to step aside and hand over to a neutral authority the responsibility of overseeing the governor’s election,” Carter said.

Kemp and Abrams are locked in a competitive battle that has been marked by tensions over race and voting rights.

Last year, Georgia passed an “exact match” voter registration law that critics argue is aimed at keeping minority voters from the polls. According to the Associated Press, 53,000 voter registration applications — most of them belonging to black voters — are on hold due to discrepancies between the information on the forms and residents’ information on file. Separately, election officials have also come under criticism for the rejection of hundreds of absentee ballots.

Abrams, who would become the nation’s first black female governor, has called Kemp an “architect of voter suppression for the last decade” and argued that he has “tried to steal the right to vote from 53,000 Georgians.”

Kemp has maintained that anyone whose registration has been put on hold can vote on Election Day so long as they bring the proper ID.

In a statement, Kemp spokesman Ryan Mahoney said that it was “sad” to see Abrams “using the former president to do her dirty work” and accused the Democrat of “trying to distract voters with another publicity stunt.”

Amy Gardner and Vanessa Williams contributed to this report.