ATLANTA — U.S. Sen. Raphael Warnock’s campaign and Democratic groups are suing the state of Georgia to overturn guidance by Republican Secretary of State Brad Raffensperger that counties can’t offer Saturday voting ahead of next month’s Senate runoff election.

The lawsuit, filed late Monday by the Democratic Party of Georgia, Democratic Senatorial Campaign Committee and the Warnock campaign, challenges the state’s finding that it would be illegal to hold early voting on Nov. 26, the day after a state holiday. The lawsuit says the state’s interpretation hurts Warnock in particular because Democrats tend to push early voting more than Republicans.

Sen. Raphael Warnock, D-Ga., left, and Republican Senate candidate Herschel Walker Associated Press photos

The race between Warnock and his Republican challenger, Herschel Walker, is headed to a Dec. 6 runoff after neither candidate won a majority of votes in the midterm election. Democrats have already secured control of the Senate but are hoping to increase their narrow margin with a Warnock victory.

“Illegal attempts to block Saturday voting are another desperate attempt by career politicians to squeeze the people out of their own democracy and to silence the voices of Georgians,” Quentin Fulks, Warnock’s campaign manager, said in a statement. “We’re aggressively fighting to protect Georgia voters’ ability to vote on Saturday.”

Raffensperger dismissed the lawsuit as politics.

“Senator Warnock and his Democratic Party allies are seeking to change Georgia law right before an election based on their political preferences,” he said. “Instead of muddying the water and pressuring counties to ignore Georgia law, Senator Warnock should be allowing county election officials to continue preparations for the upcoming runoff.”

Walker’s campaign did not immediately respond to a request for comment.

Under Georgia’s 2021 election law, there will be only four weeks before the runoff – with Thanksgiving in the middle. Many Georgians will be offered only five weekdays of early in-person voting beginning Nov. 28. And June’s primary runoffs showed time for mail ballots to be received and returned can be very tight.

Raffensperger and Deputy Secretary of State Gabriel Sterling had initially said they expected at least some counties would offer voting on the Saturday after Thanksgiving. State law requires at least five weekdays of early in-person balloting beginning Monday, Nov. 28, but also directs Georgia’s 159 counties to open early in-person voting “as soon as possible” in a runoff.

But Sterling told The Associated Press in a Friday interview that officials had researched the law and concluded that it would be illegal to hold early voting on a day after a state holiday. Thanksgiving and the following Friday are both state holidays. Raffensperger’s office followed up Saturday with an official election bulletin to the counties setting the position into writing.

The plaintiffs say Raffensperger’s interpretation “misreads” and “cherry-picks” the law.

They argue that the bar on voting after a holiday applies only to primary and general elections and not to runoffs. They say a 2017 revision of state law dropped the holiday exception for runoffs, and that reading it that way would mandate early voting on Saturday, Nov. 19, an impossibility since state officials don’t plan to certify the midterm election results until Monday, Nov. 21.

“The Secretary’s insistence that counties may not hold advance voting on November 26 therefore has no support in the law,” lawyers wrote.

The lawsuit, filed in Fulton County Superior Court, asks a judge to rule that the law doesn’t bar counties from holding advance voting on Saturday, Nov. 26 and to bar Raffensperger from interfering with counties holding voting on that day. The plaintiffs also ask for an emergency hearing and temporary restraining order.

The DSCC has sent letters encouraging counties to defy Raffensperger and schedule Saturday voting anyway. But the lawsuit notes that the State Election Board might retaliate against counties that go ahead by investigating or suspending election officials. Atlanta’s Fulton County is already under investigation after Republican lawmakers used a provision in Georgia’s 2021 election law to demand a state inquiry.

Republicans pushed through the election law in response to Donald Trump’s false claims that he had been cheated out of victory in Georgia. Republicans argued the law was needed to restore public confidence, but it shortened the period to request an absentee ballot and limited ballot drop boxes, leading to a Democratic outcry.

Saturday voting had less participation during the general election than weekday early voting, but Democrats argue that it benefits people who can’t vote on weekdays and that eliminating Saturday voting would harm Warnock “by eliminating a potential advance voting day that is likely to be used by voters who affiliate with the Democratic Party.”

The lawsuit plays out against a yearslong background of clashes over voting in Georgia. In 2018, Democrat Stacey Abrams claimed Republican Brian Kemp used his position as secretary of state to improperly hold back likely Democratic voters in their gubernatorial contest that year. The Abrams-founded Fair Fight Action lost a lawsuit over those claims.