• Candidates are making a final pitch to voters across the United States.

ATLANTA — For weeks, Brian Kemp, the Georgia secretary of state and Republican candidate for governor, has faced accusations that he is trying to suppress the minority vote in his race against Stacey Abrams. And just days ago, a federal judge ruled that the state needed to adjust elements of its so-called “exact match” voting requirement, calling them needlessly burdensome.

Now, in what Democrats said was a desperate attempt to deflect attention just two days before a crucial midterm election, Mr. Kemp used his official position Sunday to announce, with scant evidence, that the Democrats were under investigation for allegedly trying to hack the state’s voter registration files.

Democrats immediately denounced the claim as bogus and called it an abuse of power.

The controversy over voting rights, and the basic mechanics of Georgia’s electoral process, has roiled one of the nation’s marquee races. Mr. Kemp is locked in a tight contest with Ms. Abrams, the Democratic nominee, who would become the first African-American woman to lead any state if she wins. For weeks she has been accusing him of trying to suppress the minority vote and called for him to step aside as secretary of state — something he has declined to do while calling allegations of suppression “a farce.”

Mr. Kemp is a staunch supporter of President Trump, and appeared with him at a rally Sunday in Macon, Ga. In brief remarks before and during the rally, Mr. Kemp made no reference to the investigation. Mr. Trump, who has made numerous baseless claims of voter fraud in the past, spoke at length about voting issues, but did not mention the probe.