May 8 (UPI) -- The Virginia Supreme Court ruled Friday that a measure to redraw the state's congressional districts to add more Democratic seats violates the state's constitution.

On April 21, Virginia voters approved the redistricting effort by 51.33%. It would have added four districts in heavily Democratic areas, likely sending four new representatives to the House of Representatives.

The Virginia court ruled 4-3 that Democratic legislators had put the amendment to allow for a new map to voters in "an unprecedented manner" that violated the state's constitution.

"This violation irreparably undermines the integrity of the resulting referendum vote and renders it null and void," the court said.

For months, states have worked to redraw districts mid-decade to help candidates win in this fall's midterm elections. Republican states, like Texas and Missouri, have redrawn their districts to help secure more Republican congresspeople. Democratic states, like California and Virginia, have done the same to secure more Democratic seats. Other states, like Florida and Mississippi are now considering redistricting since the Supreme Court struck down parts of the Voting Rights Act.