Bernie Sanders signs copies Of "Our Revolution: A Future To Believe In" on Nov. 14 at Barnes & Noble in New York. (Theo Wargo/Getty Images)

As dusk neared, Alyssa Goldstein remained planted in the lawn chair she had set up on a busy Manhattan sidewalk shortly after 9 a.m., joining a queue of strangers who by now felt like friends.

In a few more hours, Goldstein would get what she was waiting for, and she had no doubt that it would be worth it, particularly now: a few moments with Bernie Sanders, who was coming to Barnes & Noble to promote his new book.

“I think especially after this week, you know, people had a mental breakdown,” said Goldstein, 39, who owns a mobile dog-grooming service. “Seeing Bernie again gives us hope.”

In the wake of Republican Donald Trump’s stunning presidential victory, the book tour begun Monday night by Sanders, an unabashedly liberal senator from Vermont who lost the Democratic primary, has become something more. For 600 of his fans, some of whom waited in line for 12 hours here, it served as a catharsis.

For nearly a week now, many of them have been reeling, wondering what will happen in Washington and what it will mean for the “revolution” Sanders pushed. On Monday, he urged his supporters to become more involved politically, not less.

They were taken inside in groups, led up an escalator and steered past the cafe, where they waited in another line that led to a beige curtain blocking the view of store patrons. After a chance for a photo and a few words with Sanders behind the curtain, some emerged in tears.

Goldstein, who described the senator as “insanely gracious,” said she was doing her best not to cry before leaving the store.

Others expressed their emotions in different ways. “I feel crazy, like I just took a hit of drugs or something!” yelled one perhaps 30-something woman, who declined to be interviewed as she headed down the escalator.

Some were wearing light-blue “Bernie” T-shirts from his upstart presidential campaign. One woman sported a button reading, “Talk Bernie To Me.” A college student was clad in a “Bernie onesie” decorated with dozens of images of the senator’s head.

All, it seemed, were still trying to make sense of a general election somehow lost by Democrat Hillary Clinton — one that many of them said they thought Sanders could have won if only he had been the party’s nominee.

“I think it was a terrible mistake,” said Josh Youngerman, 25, a political activist and actor from Brooklyn, who argued that Sanders would have been the stronger candidate against Trump.

With his message of economic populism, Sanders connected better than Clinton in some of the Rust Belt states that she lost, including Michigan and Wisconsin, he said.

Youngerman said he had volunteered for Sanders’s campaign in five states and logged more than 400 hours working phone banks for him — yet never met the senator before Monday night.

“It helps. It helps, for sure,” he said, quickly changing his tone. “But still, it’s pretty devastating. We have a fascist for a president.”

“It is really emotional,” Kayla Ichikawa of Queens said after she and her husband had their picture taken with Sanders behind the curtain.

Before Sanders’s primary bid, Ichikawa, 24, said she felt jaded by politics. Sanders gave her hope.

“It was already hard when he lost the primary, and then Hillary lost, too,” she said.

A public school teacher in Brooklyn, Ichikawa said she’s worried that Trump will seek to deport her students who are undocumented immigrants.

Sanders, who during his campaign was more comfortable talking about policy than posing for pictures, said he feels “an enormous sense of obligation” to help his supporters get through this stretch.

“These are hard times,” he said in an interview before posing for photos for two hours. “The answer is not despair. The answer is not to give up. The answer is to become involved.”

Trump’s victory has changed both the tone of the book tour and Sanders’s upcoming role in Washington. The book, titled “Our Revolution: A Future to Believe In,” is part campaign memoir but also very heavy on his policy prescriptions for the future.

“I like the book,” Sanders said. “Needless to say, I’m prejudiced. But I suspect . . . the reviews will not be great. There’s no gossip in it. There’s no juicy stuff in it. I know that. On the other hand, I think we need to take a very, very hard look at where we are as a country, where we have to go, and that’s what the book does.”

Anticipating a Clinton presidency, Sanders and other liberal lawmakers were preparing to push her to join with them on an array of initiatives, including tuition-free education at public colleges and universities. Now they’re preparing to spend far more time playing defense.

That has not diminished interest in what Sanders has to say. A representative of the publisher, St. Martin’s Press, said there has been an uptick in demand for the book since the Nov. 8 election.

There are 17 stops on the book tour, which includes a variety of events. Some are meet-and-greets, like the one here on Monday night, but some more substantive discussions are scheduled.

In Washington on Wednesday, for example, Sanders is planning to talk about the future of the Democratic Party in a sold-out event at a 1,500-seat auditorium at George Washington University.

“A lot of the people who will be coming out are deeply worried about the future of this country,” Sanders said. “In some cases, they’re literally worried about their own lives and what this might be for them and their families. It’s very personal. So I think the seriousness of the moment has been intensified.”

Without a Democratic president, Sanders’s voice is likely to be among those amplified. That was evident Monday during a string of New York media appearances, including stops at “The View” and “The Late Show With Stephen Colbert.”

Colbert asked Sanders if he saw overlap in the anger between the crowds he drew and those who supported Trump. Sanders allowed that there was some but said he can’t imagine that many of his supporters voted for the Republican nominee, citing offensive things he had said about women, Latinos, Muslims and other groups.

“Above and beyond the incredible bigotry of the Trump campaign, what he did is he tapped into a lot of pain and anxiety and angst the American people are feeling, which is very rarely reported in the media or understood by the public,” Sanders said.

Before the show’s taping began, Colbert visited with his audience and told them he thought Sanders was the perfect person to explain what had happened.

“I can’t think of anybody I’d rather have on the show,” he said. “I think that’s the leader of the opposition now, Bernie Sanders.”

Whether that proves true or not, Monday night showed that the loyalty of many Sanders fans has not diminished.

Tyler Brady began waiting in line at 4 a.m. for his chance to pose with Sanders for a photo. He was able to leave the scene long enough to attend an international politics lecture at New York University while others held his spot, he said, but otherwise he waited on the sidewalk all day.

“It’s one of those meet-your-heroes moments,” he said.

Brady, 18, grew up in Scranton, Pa., the kind of town where blue-collar workers tipped the scales for Trump last week. But Brady’s politics are different, partly as the result of the 75-year-old senator, whom the teenager said introduced him to the idea of democratic socialism.

“Hopefully he makes a 2020 run,” Brady said. “One can only hope.”