“I feel like I’m watching my uncle up there. Where me and Chuck Schumer — that’s like going to the dentist,” he added, referring to the Democratic leader in the Senate.

Gregory Kline, 46, a lawyer in Severna Park, Md., who is a Republican, said he did not vote for Mr. Trump but understands that part of the president’s support comes from fury at the left, particularly the media. When there is an attack by Muslim terrorists, for example, the media reaches for pundits who say most Muslims are good. But when it is a white supremacist, “every conservative is lumped in with him,” he said.

“It’s not that people are deaf and dumb and don’t see it,” he said of Mr. Trump’s sometimes erratic behavior. “It’s that they don’t care. I’ve heard rational people I really respect make the craziest apologies for this president because they are sick of getting beat on and they are happy he’s fighting back.”

Is there anything Mr. Trump could do that would change the minds of his supporters? For the most loyal, probably not. A recent Monmouth University poll found that, of the current 41 percent of Americans who approve of the job he is doing, 61 percent say they cannot see Mr. Trump doing anything that would make them disapprove of him. (A similar share of the other side says there is nothing Mr. Trump could do — other than resigning — to get them to like him.)

But for many others, support is conditional. (Mr. Trump’s poll numbers have dropped considerably since he took office in January.) Michael Dye, a 52-year-old engineer who is the treasurer for the Republican Party in Annapolis, Md., said he was “a bit stunned” that Mr. Trump had not focused more on condemning what was a large neo-Nazi march through the middle of the University of Virginia, Mr. Dye’s alma mater.

“At best it is naïve to think that the people showing up for the original protest were there simply because they were upset that this statue was being taken down,” said Mr. Dye, who said he voted reluctantly for Mr. Trump.

Of the chant “Jews will not replace us,” he said: “You can argue that it was 10 percent of the crowd. But there are those types in there and I’ve got a problem with that and I wish he’d specified that.”