By Matt Petrillo

PHILADELPHIA (CBS) — Democratic presidential nominee Joe Biden and President Donald Trump spent the weekend campaigning in key battleground states. Biden targeted Pennsylvania, spending Sunday in Philadelphia and will spend two drive-in events in Pittsburgh and also hit Ohio on Monday.

Biden’s running mate, Sen. Kamala Harris, will hold a drive-in event in Philadelphia on Monday. The senator will also hold get out the vote events in the Lehigh Valley and Luzerne County.

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Meanwhile, Trump will be holding a rally at the Wilkes-Barre/Scranton International Airport. The president will also hold rallies in Michigan, Wisconsin and North Carolina. Vice President Mike Pence will greet voters in the Pittsburgh area and Erie.

Voter turnout is expected to be huge on Tuesday, and voters are being urged to pack their patience.

“Pennsylvania has been somewhat of a swing state or battleground state for some time now,” Committee of Seventy policy director Patrick Christmas said.

Christmas, the policy director at the nonpartisan government watchdog group Committee of Seventy, is expecting a tight presidential election in Pennsylvania.

“Three million Pennsylvanians total have requested absentee and mail-in ballots. There will be a lot of people who will be voting in-person on Tuesday and between lines having to be socially distance,” Christmas said. “Some of the new procedures taking longer, for example, to have to spoil a mail-in ballot. A lot of folks will be voting provisionally. Folks should expect lines and be patient. One of the golden rules for those folks voting in-person, if for whatever they are not allowed to use the voting machine, they must vote a provisional ballot. We don’t want any registered voters turning around and going home without casting a ballot this election.”

But Christmas also says results in Pennsylvania may not come until a few days following the election.

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“Our counties cannot open the envelopes and start processing ballots, counting ballots until Election Day, 7 o’clock in the morning on Tuesday,” Christmas said. “This means we will not have a full count on Election Night. We’re going to have to wait a day or two or maybe even three days to count most of the mail-in ballots. If it all comes down to Pennsylvania, all eyes will be on us. We’re going to have to be patient and allow our local officials to count these ballots.”

For now, Christmas says many polls have Biden in the lead in the commonwealth, but the only poll that matters is the one when all the votes are counted.

“The fact that we have a lot of Democrats, a lot of Republicans and a lot of independent voters as well is what makes this a very interesting state in presidential politics,” Christmas said.

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