WATCH: Harris rallies voters at Philadelphia Community Center in swing state Pennsylvania

PHILADELPHIA (AP) — Kamala Harris said Sunday that “no one can stand by” in this year’s presidential election, capping a day of campaigning in the largest city in the crucial battleground state of Pennsylvania.

Watch Harris’ remarks in the player above.

“We are focused on the future and the needs of the American people,” Harris said, “unlike Donald Trump, who is always looking in the mirror and focusing on himself.”

Speaking at a city recreation center, the Democratic vice president singled out young voters, praising them for their “righteous impatience for change” and telling the audience there is “too much at stake” in the campaign.

“We shouldn’t wake up the day after the election and regret what we could have done in those nine days,” Harris said.

Mark Ruffalo and Don Cheadle, two actors who starred in Marvel’s “Avengers” films, were present at the rally. Harris reminded the crowd that Pennsylvania’s early voting deadline is Tuesday, advising them to “do it tomorrow if you can.”

Inspiring voters in Philadelphia, a traditional Democratic stronghold, is critical to Harris’ chances of defeating Republican nominee Donald Trump. If turnout here is low, she will have a hard time overcoming Trump’s advantages in rural Pennsylvania.

LOOK: While campaigning in Philadelphia, Harris says the US is “determined to turn the page” on hatred and division.

“Philadelphia is a very important part of our path to victory,” Harris told reporters. “This is the reason I spend my time here. But I’m very optimistic about the enthusiasm.”

Kenny Payne, 62, said Harris is going to win and “it won’t be close.” A Democratic voter said he was playing golf with a group of Republicans who say they will no longer vote for Trump.

“I think we’ll all be asleep by midnight,” he said outside the recreation center where Harris spoke.

Patrick Boe, 46, said he was confident in the city’s enthusiasm for Harris, but acknowledged his opinion may be skewed.

“I’m in a bubble here,” Bo said.

Randill Butler, the youth basketball coach who introduced Harris, said the election would take place in the “fourth quarter.”

“We can’t get tired,” she said. “We cannot be complacent.”

Harris and Tim Walz, the Minnesota governor who is her running mate, are expected to visit all seven battleground states in the coming days as part of the final campaign before the election.

LOOK: Walz speaks on reproductive rights at a campaign event in Las Vegas

While Harris was in Philadelphia on Sunday, Walz was campaigning in Las Vegas. On Monday, Walz will visit Manitowoc and Waukesha, Wisconsin, before joining Harris at a rally in Ann Arbor, Michigan, where singer Maggie Rogers is scheduled to perform.

Harris will be in the nation’s capital on Tuesday to make what her campaign calls her “closing argument” in a speech from the Ellipse, the White House lawn. This is the same location where Trump spoke on January 6, 2021, when the Republican called on his supporters to march on the Capitol.

Additional campaign stops are planned in Georgia, North Carolina, Pennsylvania, Wisconsin, Nevada and Arizona.

Megerian reported from Washington.