Republicans returned to the Supreme Court on Friday for the first time after Election Day, with an emergency application that appears to be in line with what has so far been a toothless and repetitive legal push to question the outcome of the presidential election in Pennsylvania.

The new filing from the Republican Party of Pennsylvania deals with only a small slice of Keystone State ballots: those that arrive in the mail after Election Day on Tuesday.

But Pennsylvania’s 20 Electoral College votes could give former Vice President Joe Biden the 270 he needs to win the presidency, making the state a must-win at this point for President Donald Trump.

State election officials say those ballots are not included in the tally, which by Friday afternoon gave Biden a 13,492-vote advantage, a lead that was expected to grow as the count continued.

And the Republican Party’s application asks the justices to order the state’s Democratic election officials to do something that those officials had already agreed to do, which is to keep those ballots separate from the ballots that arrived on or before Election Day.

Election law expert Rick Hasen, a professor at the University of California, Irvine School of Law, tweeted: “This is theater.”

The new filing, while giving the impression that it opens a new legal front at the nation’s top court as Trump wants to do, actually piggybacks on an ongoing case that started before Election Day.

Republicans had asked the Supreme Court to stop a state supreme court ruling that allowed Pennsylvania to tally mail-in ballots that arrive up to three days after Election Day amid concerns that many residents would vote by mail in a pandemic during which mail delivery has slowed.

The Supreme Court declined to decide the issue before the election, but that didn’t mean the case was over. As part of that Oct. 28 decision, Justice Samuel A. Alito Jr. wrote that Republicans could still ask the Supreme Court to “order that ballots received after election day be segregated so that if the State Supreme Court’s decision is ultimately overturned, a targeted remedy will be available.”

Democratic state officials already wrote the Supreme Court ahead of that decision on Oct. 28 to say that they had issued guidance to county boards of election to keep those late-arriving ballots segregated.

In the emergency application Friday, the state Republican Party asked for an order that requires Secretary of State Kathy Boockvar and the county boards of elections “to log, to segregate, and otherwise not to take any action” related to the late-arriving ballots.

County boards of elections may choose not to follow Boockvar’s guidance about how to handle those ballots, the application states. The party told the justices that 25 counties did not respond to queries about whether they are following the guidance.

“Given the results of the November 3, 2020 general election, the vote in Pennsylvania may well determine the next President of the United States — and it is currently unclear whether all 67 county boards of elections are segregating late-arriving ballots,” the application states.

The application asks for the order “immediately” and for a ruling “as soon as possible.”

The question about whether election officials can change rules to allow the counting of ballots received after Nov. 3 highlights how courts have grappled with the way states are dealing with an election during the worsening pandemic.

This Pennsylvania case always had the potential to become a big deal in an extremely close election where the ballots that arrived late ultimately determine not only who wins Pennsylvania but also which candidate wins the White House. It was unclear Friday whether such a situation would occur.

The Trump campaign on Thursday had already asked the Supreme Court if it could join the pending Republican lawsuit.

There are around 100,000 uncounted mail ballots in Pennsylvania, which Biden has won at a rate of about 75 percent, and his lead will go up, said NBC political correspondent Steve Kornacki, who has become a leading voice in the political math of the count.

But it’s unclear how much that lead will go up because some could not be counted, and there are 100,000 provisional ballots, an unusually high number that have not favored Biden, Kornacki said.