Republican lawmakers filed a lawsuit Thursday seeking to block Maryland’s newly approved congressional redistricting amendment from reaching voters in November, one day after Democratic Gov. Wes Moore signed the measure.

The lawsuit says lawmakers approved the amendment too late to meet state election deadlines and cannot bypass those requirements by writing an exception into the legislation.

The suit was filed in Anne Arundel County Circuit Court by all seven members of the conservative Maryland Freedom Caucus, along with Senate Minority Leader Steve Hershey, Senate Minority Whip Justin Ready and Mike Howell, president of the conservative advocacy group the Oversight Project.

The challenge comes after the Democratic majority General Assembly approved House Bill 2100 during a three-day special session this week. Moore signed the measure Wednesday, setting up a statewide vote Nov. 3.

The amendment would not redraw Maryland’s congressional districts or affect this year’s congressional elections. Instead, it would change the constitutional rules governing future congressional maps, including separating the standards for congressional districts from those that apply to state legislative districts. It also would allow the General Assembly to give the Maryland Supreme Court authority to hear challenges to congressional maps.

If approved by voters, the amendment could clear the way for lawmakers to redraw Maryland’s congressional map before the 2028 election. Democrats hold seven of the state’s eight U.S. House seats, with Republican Rep. Andy Harris holding the state’s only Republican congressional seat.

At the center of the lawsuit is timing.

Maryland law requires statewide ballot questions to be prepared and certified by July 1 before a general election. The complaint says that deadline had already passed before lawmakers approved HB2100.

The lawsuit also points to requirements for public notice and review of proposed ballot questions. The plaintiffs say the shortened timeline prevents the state from following the normal process before the November election.

Lawmakers sought to address those deadlines by adding language saying the amendment would go before voters “notwithstanding any other provision of law.”

The plaintiffs say that language cannot override Maryland election law.

“The combination of statutory violations is neither accidental nor insignificant,” the complaint states.

The lawsuit also raises a separate constitutional argument. Maryland requires proposed constitutional amendments to address a single subject. The plaintiffs contend HB2100 violates that requirement because the provision overriding election laws is separate from congressional redistricting.

They also say the proposed ballot language does not clearly tell voters what the amendment would do.

The plaintiffs are asking the court to prevent state officials from certifying or placing the amendment on the Nov. 3 ballot. If ballots have already been printed or voting has begun, they want the court to prevent votes on the amendment from being counted or certified.