Voters across the country may have to wait days to find out whether Vice President Kamala Harris or former President Donald Trump wins Pennsylvania’s 19 electoral votes, election officials say.

But Pennsylvania is literally the key state to decide who wins the White House once Tuesday’s votes are counted.

“We ask for your patience as our counties work day and night, doing it as quickly as they can and with integrity,” Pennsylvania Secretary of State Al Schmidt said during a televised interview last month.

Election officials cautioned that the delays are not a cause for concern, but rather the result of Pennsylvania law that limits when counties can begin counting what could be more than 2 million mail-in ballots.

There was a four-day wait for those results four years ago as counties counted nearly 3 million mail-in ballots. Fewer mail-in ballots were requested by voters before this election, and officials’ experience gained from four years of handling mail-in ballots raised the confidence level for a faster turnaround to complete the count this time.

But the results will likely take days rather than hours.

“If we have 5 percent of the ballots left by midnight, clearly we’re going to wait another day or two to call in Pennsylvania,” said Jeff Greenburg, a former Mercer County elections director who now serves as alderman of the Committee of Seventy. a non-partisan non-profit election watchdog group based in Philadelphia.

“Patience is the watchword. The election was not over at 8:01 p.m. We have to wait for the certification. It’s not going to be as extended as it was in 2020. I’m confident that the counties are ready and in a much different place than we were in 2020,” Greenburg said.

Under state law, Pennsylvania counties cannot begin processing mail-in ballots until 7 a.m. on Election Day. For the past four years, counties have lobbied to no avail for state lawmakers to change voting laws to allow mail-in ballots to be counted earlier.

State subsidies awarded in recent years to purchase new equipment and hire additional staff are expected to speed up the process.

In Allegheny County, where more than 250,000 mail-in ballots could be cast, officials said equipment is available to open up to 50,000 mail-in ballot envelopes per hour. All postal ballots are expected to be counted by 8pm when the polls close.

In Westmoreland County, where it took more than 24 hours to count more than 50,000 mail-in ballots in 2020, officials said the added equipment and expertise will speed up the process. Nearly 60,000 Westmoreland voters requested mail-in ballots this fall, and as of Thursday, more than 44,000 had been returned.

Director of Elections Greg McCloskey said the county expects all mail-in ballots to be counted by 10 p.m. on Election Day.

Mail-in ballots accounted for about half of the votes cast in 2020. It will be a smaller percentage of all votes cast this year, officials said.

Millions of Pennsylvanians are still expected to vote at the polls. There are 1,327 polling places in Allegheny County. Results downloaded to flash drives will be transported to the county’s electoral warehouse and uploaded to the county’s computer system.

Westmoreland County has 306 precincts, and those votes will be taken to the courthouse in Greensburg on flash drives, with results posted to the county’s website throughout the night. Officials say they expect totals from that day’s vote to be completed by midnight.

Polls are scheduled to close at 8pm on election day, but votes could still be cast later in the evening. The polls will remain open until everyone in line, even after the official closing time, has been able to cast their ballots, officials said.

The potential for large numbers of provisional ballots could also lead to delays in declaring the winner. Voters whose eligibility is in question or who requested mail-in ballots but choose to vote in person at the polls instead may vote provisionally on Election Day. Officials have seven days after the election to assess whether those ballots can be counted.

About 100,000 provisional ballots were cast in Pennsylvania in 2020, where the presidential race was decided by just over 80,000 votes.

State law also allows ballots cast by overseas voters and members of the military to be counted if they arrive within seven days of the election.

“We expect thousands of provisional and overseas ballots to be counted, and that could take another day or two,” Greenburg said.

Officials said they were confident in the process.

“This is our Super Bowl and we can’t screw it up,” Westmoreland County Commissioner Sean Kertes said.