HARRISBURG, Pa. (AP) — With six days until Election Day, Pennsylvania's top elections official on Wednesday urged voters in the presidential battleground state who have one of the roughly 1 million mail-in ballots outstanding to drop it off in person rather than mail it.

In addition to concerns over Postal Service delays, litigation in front of the U.S. Supreme Court is raising doubts over the timing of the deadline for counties to receive mail-in ballots.

The state Republican Party is asking the court to reinstate an Election Day deadline for receiving ballots, rather than the state court-ordered Nov. 6, three days after the election.

It is unclear how quickly the court will take up the case after it said Wednesday said it would not grant a quick, pre-election decision. But, in a sign of the uncertainty brewed by the litigation, Pennsylvania told counties on Wednesday to set aside and not count those ballots arriving after polls close until they get further direction from the state. It remained unclear whether those ballots will ultimately be counted.

“At this point we are not recommending that anybody put their ballots in the mail, just drop it off in person," Secretary of State Kathy Boockvar told reporters Wednesday. "We really recommend that you drop it off in person.”

The deadline to apply for mail-in ballots passed on Tuesday. Voters applied for almost 3.1 mail-in or absentee ballots, with about 2 million returned thus far, election officials say.

There are a variety of ways to drop off mail-in ballots, including at secure election drop boxes, county election offices and other county-designated drop-off locations.

Boockvar also urged counties to begin the laborious task of processing mail-in and absentee ballots on Election Day — tasks like removing ballots from their outer and inner envelopes — so that they can be more quickly scanned and tabulated.

Counties expect to need up to three days after Election Day to tabulate the vast majority of mail-in ballots, whether they are dropped off or mailed, with expectations that many mail-in votes will not be counted the night of the election.

Gov. Tom Wolf and his fellow Democrats in the state Legislature had pressed for legislation allowing counties to process mail-in ballots before Election Day, but Republicans blocked it.

That could leave the results of many contests, including Pennsylvania's presidential election result, in doubt for days after polls close.

The drawn-out counting is shadowed by President Donald Trump's impossible demand this week that all votes be counted on election night and a winner declared in his contest with former Vice President Joe Biden.

Counties can start opening what could be more than 3 million mail-in ballot envelopes starting Tuesday at 7 a.m., when Election Day polls open, but they cannot start tabulating them until polls close at 8 p.m. that night.

Philadelphia, the state's most populous city, and Pennsylvania's most heavily populated counties plan to begin tabulating mail-in ballots on election night with the in-person results from polling places.

Some less-populated counties do not plan to start processing or tabulating mail-in ballots until Wednesday.

That includes Cumberland County, in suburban Harrisburg, and northeastern Pennsylvania’s Monroe County.

Officials in both counties said they need to be able to concentrate on managing the in-person vote on Election Day.

Cumberland County said it will not begin processing or tabulating some 60,000 mail-in and absentee ballots until Wednesday. Monroe County will do some processing of about 38,000 mail-in and absentee ballots on Tuesday, but tabulating will not begin until Wednesday, said Sharon Laverdure, the county commission chair.

In southwestern Pennsylvania’s Greene County, officials there will not begin digging into roughly 4,600 mail-in and absentee ballots until Wednesday, said Commissioner Chair Mike Belding.

They don’t have the staff or the room to tabulate the in-person vote and mail-in ballots at the same time, Belding said.

“Our perspective is to do everything we do with 100% accuracy, and we wouldn't be able to to that if we were going to do two activities of that scope at the same time,” Belding said.

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