It was Pennsylvania that decided the last election in a process that took days because state law prohibits election workers from opening hundreds of thousands of mail-in ballots until polls close on Election Day. It led to protests and conspiracy theories - which Trump spouts to this day.
"These elections have to be decided by 9:00, 10:00, 11:00 on Tuesday night - bunch of crooked people," Trump said.
"It is meant to distract from the fact that we have and support free and fair elections in our country. We did in 2022. He lost," said Vice President Kamala Harris.
On Sunday, Harris was in Michigan, but she and Trump will be back in the Keystone State on Monday. Each candidate must win Pennsylvania - they have been there dozens of times, collectively spending more than half a billion dollars for a race that polls suggest is tied.
Though Harris got some surprise good news on Sunday in reliably Republican Iowa, a local pollster is suggesting she is ahead of Trump there.
Back in the Democratic stronghold of Philadelphia, Harris needs all the votes she can get - still, it could be razor-tight.
Harris supporter Ben Goff owns an art gallery, and he says he is convinced it won't be that close.
"I don't think it is, because I've been talking to a lot of people and asking them, I really believe people are fed up with Trump that they want a change. I think that she's in the right place at the right time," Goff said.
The Harris campaign has announced which performers will be in attendance for a massive Get Out the Vote concert on the Benjamin Franklin Parkway in Philadelphia on Monday night, the night before Election Day 2024.
Kamala Harris' campaign is hosting the concert, which is set to begin at 5 p.m. Monday.
The event is expected to have performances or remarks by DJ Cassidy, Fat Joe, Freeway and Just Blaze, Lady Gaga, DJ Jazzy Jeff, Ricky Martin, The Roots, Jazmine Sullivan and Adam Blackstone, and Oprah Winfrey.
The vice president is also said to be among the attendees.
Trump has yet to announce his plans for the eve of the election.
Join Eyewitness News on Monday at 2 p.m. for our 'Vote 2024' special as we break down the key races and discuss the election night impact in our area.
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