The case is part of a national redistricting fight with high stakes for the November midterm elections

• Sign up for the Breaking News US email to get newsletter alerts in your inbox

Virginia supreme court justices on Monday questioned whether the state’s Democratic-led legislature complied with constitutional requirements when it sent a congressional redistricting plan to voters, in a case that carries high stakes for the balance of power in the US House.

The new districts, which could net Democrats four additional seats, won narrow voter approval last week. But a Republican legal challenge contends the general assembly violated procedural rules by placing the constitutional amendment before voters to authorize the mid-decade redistricting. If the court agrees that lawmakers broke the rules, it could invalidate the amendment and render last week’s statewide vote meaningless.