The Trump administration asked the Supreme Court to mandate that California separate ballots of more than 20,000 voters the government suspects are "likely" non-citizens.

The big picture: A federal appeals court rejected the administration's bid to set aside mail ballots last week, erecting another roadblock in the DOJ's pre-election quest to demand the state root out claims of voter fraud in the final days of the midterm elections.

Driving the news: "Once California commingles the challenged ballots with lawful ones, there is no way to get the challenged ballots back," the DOJ wrote in an application filed to the high court.

"The only way to preserve the district court's ability to grant relief to the United States after a full merits proceeding, therefore, is to segregate the challenged ballots now," the application, signed by Solicitor General D.…