EXCLUSIVE: DNC joins Supreme Court voting case, blasts RNC efforts as 'wholly un-American'

FIRST ON FOX: The Democratic National Committee filed a Supreme Court amicus brief Thursday seeking to counter the Republican Party in a major election law case this year — setting the stage for a high-stakes court clash that could determine the fate of millions of mail-in ballots nationwide. 

The Supreme Court agreed in November to take up the case, Watson v. Republican National Committee, which centers on states' ability to count mail-in ballots that are received within five days of an election.