Kamala Harris makes final appeal to voters during late-night election rally in Philadelphia

With its 19 electoral college votes, Pennsylvania has been at the centre of this year's presidential campaign

Democratic presidential nominee Kamala Harris speaks during a campaign rally in Philadelphia, Pennsylvania. Reuters

Latest updates: Follow our full coverage on the US election

Tens of thousands of Kamala Harris supporters thronged downtown Philadelphia on Monday to hear the US Vice President deliver remarks at her final rally before election day,

"America comes down to this one more day, just one more day in the most consequential election of our lifetime, and the momentum is on our side," she said.

Ms Harris spoke after remarks by her husband Doug Emhoff, Oprah Winfrey, and performances by Lady Gaga and will.i.am.

Ms Harris and her Republican rival Donald Trump headed to Pennsylvania to urge supporters to vote on Tuesday. The north-eastern state has the largest share of votes in America's Electoral College system out of any of the seven battleground states expected to determine the outcome.

"The race ain't over yet, and we must finish strong," Ms Harris said. "And this could be one of the closest races in history, every single vote matters."

The Harris campaign held a series of "Vote for Freedom" rallies in cities across many states – including Atlanta, Georgia, Detroit, Michigan, Las Vegas, Nevada; Phoenix and Arizona.

The rallies featured musicians such as Katy Perry, James Taylor, Christina Aguilera and Jon Bon Jovi.

"Tonight, then, we finish as we started, with optimism, with energy, with joy, knowing that we the people have the power to shape our future and that we can confront any challenge we face when we do it together," Ms Harris said of her short 107-day campaign that started with her boss President Joe Biden ending his re-election bid in July.

Darla LaSure, a New Jersey resident who travelled to Philadelphia to attend the Harris rally, said she was supporting the Vice President because she believes Mr Trump would undermine American democracy if re-elected.

“I truly believe our democracy is on the line,” Ms LaSure told The National. “I really do think this is going to be a deciding factor of which way our country goes.”

Ms Harris has said that her rival wants to shred the US Constitution, rule like a dictator and has expressed admiration for Adolf Hitler and his Nazi generals.

The Democrat highlighted how she spoke "where the foundation of our democracy was forged, and here, at these famous steps, a tribute to those who start as the underdog and climb to victory".

Opinion polls suggest Ms Harris and Mr Trump are effectively tied, and Ms LaSure said she was upset the race is so close.

“It's not just the freedoms of women, but the freedoms of our country and our children and our future generations are all at risk now,” she said. “Just to see all the rhetoric and to see how evenly the race is, it's just upsetting to think that the country could go either way.”

Jose and Lillian Decos drove down from neighbouring Delaware to attend Monday’s closing rally.

Even though they couldn’t get anywhere near the event, the Decos were thrilled to be nearby.

“I'm so happy to see so many people, so many young people, so many families, so many people of different colours, ethnicities, coming here,” said Ms Decos, 35, who is originally from Ukraine.

Her husband added: “It feels like the future of America here.”

“From taxes to abortion to everything, I haven’t seen one good thing from Trump,” Mr Decos added.

With 19 electoral college votes, Pennsylvania is the biggest prize of any battleground state. A Trump victory here would puncture the Democrats' “blue wall” and make it much harder for Ms Harris to win the necessary 270 votes.

Michelle Chris, 57, said she is voting with her granddaughter in mind.

“I want her to have more rights than I did,” she said, referring to the 2022 Supreme Court ruling that ended the federal right to an abortion.

The queue to get into the event snaked around several city blocks, with many in the crowd resigned to watching Ms Harris from beyond a fenced perimeter.

A lone supporter of third party candidate Jill Stein was met with a chorus of boos when he suggested that without an arms embargo against Israel, Democrats should not vote for Ms Harris.