WASHINGTON (AP) — The Supreme Court has upheld a lower court ruling that struck down 28 state House and Senate districts in North Carolina because they violated the rights of black voters. But the justices rejected the court’s order to redraw the districts and hold a special election.

The action by the justices Monday sends the matter back to the lower court, which could order new districts in time for the regular cycle of elections in 2018.

Democrats hope new district maps will help them break the Republican stranglehold on the state legislature.

Democrats need to capture three House seats or six Senate seats currently held by Republicans to eliminate the GOP’s veto-proof majorities. That would enhance the power of Democratic Gov. Roy Cooper.

A panel of three federal judges in North Carolina that struck down the districts as illegal racial gerrymanders had ordered the drawing of new districts in time for special elections this year. But the Supreme Court blocked the order for the new districts. The matter is back in the hands of the lower court.

The high court’s action follows last month’s ruling in which the justices struck down two North Carolina congressional districts because they diminished the voting strength of the state’s black residents.

The districts were initially drawn in 2011 when Republicans controlled the legislature, as they do now. Civil rights groups and black voters challenged the districts, complaining that they packed too many black voters into some districts to make surrounding districts whiter and thus more likely to elect Republicans.

Cooper defeated Republican Gov. Pat McCrory in November.