The Pennsylvania Supreme Court reiterated its order Friday that prevents county election officials from counting absentee ballots with missing or incorrect dates, overturning a lower-court decision in Philadelphia that would have allowed the ballots to be counted.

The unsigned decision said courts shouldn’t change election rules so close to the Nov. 5 election. Litigants could continue to fight the case later.

The stakes were potentially significant in the key swing state because 2.1 million requests for absentee ballots were approved and nearly 1.5 million had been returned through Wednesday. But the portion with date mistakes won’t be known until ballots are processed on Election Day on Tuesday.

The decision was one of several in Pennsylvania dealing with how absentee ballots are processed in the key battleground state. Republicans have said they are fighting to enforce election laws while Democrats have argued they were trying to suppress votes.

Republican National Committee Chairman Michael Whatley called the decision “another big win for election integrity.”

“The Pennsylvania Supreme Court upheld the law, and the dated ballot requirement will be in effect for this election,” Whatley said. “Democrats have repeatedly tried to eliminate this important ballot safeguard, and we have stopped them each time.”

State law prohibits counting ballots with missing or mistaken dates. The state Supreme Court upheld the law in September and October.

The lawsuit was a fight over whether to count 69 such ballots in a special election in September in Philadelphia.

Commonwealth Court Judge Ellen Ceisler wrote for the 3-2 majority Wednesday the ballots should be counted despite “meaningless dating provisions” in state law.

But Republicans appealed her decision. The timing of the case was contentious because votes were already being cast. The decision threatened to confuse voters, according to judges who dissented from the decision.

Justice Kevin Dougherty agreed with the high court’s decision and said it “sends a loud message to all courts” not to substantially alter laws and procedures during an ongoing election.