Pennsylvania Democrats Wonder How Far Left is Too Far in 2020

“I love Joe, but I think that with the new era, and the MeToo and all that, Joe has some skeletons in his closet,” said Jane Lyons, 63, a hospital administrative assistant in suburban Pittsburgh. “There are people coming up under me that won’t tolerate it.”

As the president’s former lawyer Michael D. Cohen on Wednesday called Mr. Trump a racist, a cheat and a con man in House testimony, the solidity of the president’s base was on display here, especially the resentments of white working-class voters who turned out in droves for him in 2016.

“We had eight years of nothing,” said Diane Pappert, 75, a retired school guard, referring to President Barack Obama, “and this guy’s trying to clean up everybody’s mess.”

Her daughter Angie Hughes, 55, a nurse, had cast the first vote of her life for Mr. Trump. She said she would never vote for a Democrat because she believed that the party favored generous welfare benefits. “When you see people who have three, four, five children to different fathers, they have no plans of ever going to work,” she said.

Lou Iezzi, 68, who still works at an auto garage he opened at 19, had voted Democratic for decades before casting a ballot for Mr. Trump. He liked the way he sounded as if he were on the next barstool, and Mr. Iezzi chuckled approvingly recalling Mr. Trump’s dismissive remarks about the newscaster Megyn Kelly in 2015 that were widely interpreted as referring to menstruation.

Mr. Iezzi could vote for a Democrat in 2020 if the nominee “sounds like he’s talking honestly,” he said. His choice of the male pronoun was deliberate: “I just can’t see a woman running this country.”

Rob Kopler, a retired deputy sheriff, who agrees with the president on a border wall, voted for him in 2016, but in the midterms he supported Mr. Lamb and Gov. Tom Wolf, a Democrat.