In a sweeping decision that is likely to have national implications, a federal court ordered the state of North Carolina on Tuesday to redraw its unconstitutionally gerrymandered voting maps and hold special elections in 28 districts by next fall.

The decisive ruling may upend the political makeup of the key southern swing state by ending the practice—championed by Republican leaders—of drawing maps that limit the voting power of African Americans.

Though North Carolina’s popular vote has been split nearly evenly between the Republican and Democratic parties in recent elections, Republicans hold the vast majority of seats in the state assembly. This is, in part, because they drew their own district maps so that African American voters are grouped into small, oddly shaped districts that make the surrounding districts whiter and therefore easier for Republicans to win.

The court mandated that new maps be drawn by March and the election be held by November.

“While special elections have costs, those costs pale in comparison to the injury caused by allowing citizens to continue to be represented by legislators elected pursuant to a racial gerrymander,” the judges wrote.

Bob Phillips, the executive director of Common Cause North Carolina, called the court’s ruling this week a “golden opportunity” to create a system in which no party controls the redistricting process and such conflicts of interest are impossible.

“We strongly urge lawmakers to pass that independent redistricting plan when they return for their new session in January, so that North Carolina citizens can finally have confidence that their legislative districts are drawn in a fair, impartial and constitutional way that avoids further confusion and delay,” he said.

The lead plaintiff in the lawsuit, retired elementary school teacher Sandra Covington, testified that she “was plucked out of my district and placed into another district simply because of my race.”

The Federal Court found North Carolina’s Gerrymandered Maps Unconstitutional.

North Carolina Republicans reacted by declaring “they will appeal” the court ruling, calling it a “gross overreach” by the court. ShareTweet