Employee holds bundles of mail-in ballots to be counted in Pennsylvania, November 4, 2020.

The Pennsylvania Supreme Court on Saturday rejected an election challenge spearheaded by U.S. Rep. Mike Kelly, who argued that a law permitting no-excuse mail voting violated the state Constitution.

Kelly, along with several other Pennsylvania Republicans, sought to invalidate millions of mail-in votes, which could have ceded a key state won by President-Elect Joe Biden to President Donald Trump.