The California map would take effect only a Republican state moves forward, and it would remain through the 2030 elections. After that, Democrats say they would return mapmaking power to the commission approved by voters more than a decade ago.

The suit comes after the California Supreme Court rejected last week an earlier effort by Republicans challenging the redistricting push.

California Republicans announced a legal challenge Monday against Gov. Gavin Newsom’s (D) effort to redraw congressional lines in the state, days after the state Legislature approved a redistricting ballot measure to go before voters this fall.