Virginia’s Supreme Court justices questioned whether the state legislature properly followed constitutional rules when approving a congressional redistricting plan that voters narrowly passed.

The plan could give Democrats up to four additional House seats, but Republicans argue the amendment process was flawed because lawmakers voted too late during an election period.

The court is considering whether “election” includes early voting, which could invalidate the legislature’s actions and nullify the voter-approved map.

The case is part of a broader national redistricting fight between Democrats and Republicans ahead of the midterm elections, The Guardian has reported.

A ruling has not yet been issued, and additional legal challenges to the map are still ongoing.