PHILADELPHIA — Kamala Harris said Sunday that “no one can sit on the sidelines” in this year’s presidential election, capping a day of campaigning across the largest city in the crucial battleground state of Pennsylvania.

“We are focused on the future and we are focused on the needs of the American people,” Harris said, “as opposed to Donald Trump, who spends full time looking in the mirror focused on himself.”

Speaking at a city recreation center, the Democratic vice president singled out young voters, praising them for being “rightly impatient for change,” and told the audience that “there is too much at stake.”

“We must not wake up the day after the election and have any regret about what we could have done in these next nine days,” Harris said.

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

Energizing voters in Philadelphia, a traditional Democratic stronghold, is crucial for Harris’ chances of beating Republican nominee Donald Trump. If turnout falls short here, she’ll struggle to overcome Trump’s advantages in Pennsylvania’s rural areas.

“Philadelphia is a very important part of our path to victory,” Harris told reporters.

Kenny Payne, 62, said Harris is going to win and “it won’t be close.” The Democratic voter said he plays golf with a group of Republicans who say they won’t vote for Trump again.

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

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

“I’m in a bubble here,” Boe said.

Randyll Butler, a youth basketball coach who introduced Harris, said the election was in the “fourth quarter.”

“We cannot get tired,” she said. “We cannot get complacent.”

The Democratic coalition relies on voters of color, and Harris’ itinerary on Sunday reflected that focus. She began the day with the Black congregation at the Church of Christian Compassion, where she said the United States is “determined to turn the page on hatred and division.”

Harris drew on the story of the Apostle Paul, who overcame difficulties to spread the word of Jesus.

“In hard times when we may grow weary in doing good, we must remember the power that works within us, the divine power that transformed Paul’s life, guided him through shipwreck and sustained him through trials,” Harris said.

W. Lonnie Herndon, the church’s senior pastor, followed her remarks with a sermon about compassion and how “strong people never put others down, they lift them up.”

“We are going to get out and vote,” he said as Harris listened. “And let me be crystal clear. We are not electing a pastor. We are electing a president that will deal with these divided United States, bring us back together.”