Rather than saying that President Donald Trump's order is legal, the high court said Monday it was too early for Democratic-run states to challenge it in June, when they convinced a federal judge in Boston to freeze the order for November's election.

"The U.S. Secret Service is aware of the video and investigates anything that can be perceived as a threat toward our protectees," Secret Service spokesman Nate Herring said in a statement.

The U.S. Postal Service laid out how it would implement the order last week, but time is running short to impose major changes with some states beginning to send mail ballots to voters in just a few weeks.