The Georgia NAACP and more than a dozen other civil rights and clergy members hand-delivered a letter of protest Thursday to Georgia Secretary of State Brian Kemp, after he alleged possible fraud by Democratic-backed voter registration group.

In the letter, they said they “sincerely hope” Kemp was not trying to “silence our voices and thwart efforts to register and engage minority voters in Georgia.”

Kemp, a Republican, announced an investigation after he said he received "numerous complaints" about voter registration applications submitted by the New Georgia Project. State House Minority Leader Stacey Abrams, D-Atlanta, founded the group in November with a goal of registered 100,000 new voters by the state's Oct. 6 registration deadline.

They also noted the state's GOP leadership has also been critical of decisions in DeKalb, Fulton and Lowndes counties to hold early voting this fall on Sundays. State Sen. Fran Millar, R-Dunwoody, who vowed to "eliminate this election law loophole," received national criticism for comments that included a plea for "more educated" voters.

The general election, which features hotly contested races for the U.S. Senate and the governor’s office, is Nov. 4.