Donald Trump and Kamala Harris held competing rallies across Pennsylvania on Monday, making their final pitches in the key swing state as polls indicate an extremely close contest.

The two candidates laid out starkly contrasting visions for America’s future on the eve of election day. Trump rambled through dark and dystopian speeches painting migrants as dangerous criminals while also launching personal attacks on a number of high-profile Democratic women. Harris delivered a more positive closing argument, shifting focus away from the threat posed by the ex-president, who is not mentioned in her final ad, and insisting “we all have so much more in common than what separates us”.

Trump, at times appearing hoarse and low-energy, scheduled four rallies on Monday: one in Raleigh, North Carolina, two in Pennsylvania and a late-evening event in Grand Rapids, Michigan. He has continued to boast about his crowd sizes, but reports suggest some of his final events have been plagued by empty seats and early departures from audience members during his lengthy, meandering speeches.

Harris stayed in Pennsylvania with several rallies and events in the critical state that could decide the election. Lady Gaga, Oprah Winfrey, Ricky Martin and other celebrities were slated to appear at her final event at the Philadelphia Museum of Art, where the famous steps from the Rocky movie were lit up blue and a large “President for All” banner was displayed.

As the Harris campaign and its surrogates have continued to appeal to female voters, Trump revived familiar insults against notable women, sometimes with violent language.

In North Carolina, he attacked former first lady Michelle Obama, saying: “She hit me the other day. I was going to say to my people, am I allowed to hit her now? They said, take it easy, sir.” He also suggested the Democratic congresswoman Nancy Pelosi should have been jailed for ripping up a copy of his 2020 State of the Union address: “She’s a bad, sick woman, she’s crazy as a bedbug.”

And Trump repeated his line that Harris is a “low IQ individual”, followed by an incoherent tangent seemingly imagining her struggling to sleep: “I don’t want to have her say, You know, I had an idea last night while I was sleeping, turning, tossing, sweating,” he said, without finishing the sentence.

Trump leaned into his taunts as he continues to face scrutiny over his recent comment suggesting that Liz Cheney, the former GOP congresswoman and a Harris supporter, should face rifles “shooting at her”. Appearing on ABC’s The View on Monday, Cheney said, “Women are going to save the day” on Tuesday.

In North Carolina, Trump also threatened the newly elected president of Mexico, Claudia Sheinbaum, suggesting he would impose tariffs on all Mexican goods “if they don’t stop this onslaught of criminals and drugs” – part of his trade proposals that economists have warned could significantly raise costs for US consumers.

Later in Reading, Pennsylvania, Trump fantasized about wrestlers who could “take the migrants in a fight”. He repeated racist tropes about immigrants and affirmed his threat of unprecedented mass deportations, saying Tuesday would be “liberation day”. He falsely suggested Democrats support “open borders” so undocumented people can fraudulently vote.

He later spoke of the boxer Mike Tyson and seemingly in response to a comment from an audience member, suggested Tyson take on the vice-president: “That guy could fight … Put Mike in the ring with Kamala.”

At around the same time, Harris was rallying in Allentown, roughly 40 miles away, critiquing Trumpism without directly naming her opponent: “America is ready for a new way forward, where we see our fellow American not as an enemy but as a neighbor. We are ready for a president who understands that the true measure of the strength of the leader is not based on who you beat down. It is based on who you lift up.”

Later, Trump’s running mate, JD Vance, earned loud applause at a rally in Georgia, when he attacked Harris by bringing up Joe Biden’s recent gaffe, in which he appeared to call Trump supporters “garbage”.

“In two days, we are going to take out the trash in Washington DC, and the trash is named is Kamala Harris,” said the Ohio senator, in a remark that was condemned by Democrats and pundits.

The back-and-forth trash talking originated with a comedian’s racist joke at Trump’s recent New York rally, calling Puerto Rico a “floating island of garbage”, a comment that many Harris surrogates cited on Monday while appealing to Puerto Rican voters in Pennsylvania.

The vice-president also stopped at a Puerto Rican restaurant with Congresswoman Alexandria Ocasio-Cortez and directly joined canvassing in a residential area in Reading, telling voters at one home: “I wanted to go door-knocking!”

By his evening rally in Pittsburgh, Trump returned to his crowd size obsession, making false claims about low turnout at Harris’s nearby rally that hadn’t yet begun. He then mocked Beyoncé, who rallied for Harris in Texas: “Everyone’s expecting a couple songs and there were no songs. There was no happiness.” He added, “We don’t need a star. I never had a star.”

The final scramble to turn out voters comes as Trump continues to make false claims about voter fraud, raising fears about how he might challenge the results if Harris wins. In a call with reporters on Monday, the Harris campaign said it was prepared to combat any efforts by Trump to discredit the outcome.

“We have hundreds of lawyers across the country ready to protect election results against any challenge that Trump might bring,” said Dana Remus, a senior campaign adviser and outside counsel. “This will not be the fastest process, but the law and the facts are on our side.”

Legal challenges were designed to undermine faith in the electoral process, she added: “Keep in mind that the volume of cases does not equate to a volume of legitimate concerns. In fact, it just shows how desperate they’re becoming.”

There are also growing fears that political violence will escalate on election day and beyond, as misinformation and conspiracy theories are expected to spread while counting is under way. Election officials in one Nevada county said on Monday that threats have become so severe that polling places have installed “panic buttons” to automatically call 911 in emergencies.

At Trump’s Pittsburgh rally, Michael Barringer, a 55-year-old coalminer, expressed his disdain for undocumented immigrants in explaining his support for Trump: “You’ve got millions and millions of illegal aliens crossing the border. They don’t speak English. They don’t say a pledge allegiance to the flag. They freeload off of us. I’m all for legal immigration, but not coming across the border illegally, taking American jobs.”

Elizabeth Slaby, 81, was the first in line at Harris’s Allentown rally, arriving at about 6am. She said she was a registered Republican for more than 50 years, but changed her registration after the January 6 attack: “I never thought I’d see a woman president and now I’m so, so excited.”

Lauren Gambino, Sam Levine and David Smith contributed reporting

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