Howard Schultz’s book launch — and potential presidential bid — is off to a rough start.

Just one day after announcing that he was preparing to run for president as a third-party candidate, the former Starbucks CEO kicked off a nationwide tour Monday evening to promote his new book. He had barely begun to speak at a Barnes & Noble in New York when a protester interrupted.

“Don’t help elect Trump, you egotistical billionaire!” the unidentified bearded man yelled, adding an expletive. “Go back to being ratioed on Twitter!”

The brief disruption summed up the animosity and outright hostility that Schultz has faced since Sunday, when he told CBS’s “60 Minutes” that he was seriously considering running for president as a centrist independent. Shortly after declaring his intentions, the billionaire coffee-chain founder was mocked by President Trump, who tweeted Monday that Schultz lacked the “guts” or the intelligence to become president. Schultz was also rebuked by countless Democrats, who fear that Schultz would split an anti-Trump vote in 2020. So far, he has posted four tweets to his newly minted Twitter account, all of which have received thousands more angry replies than endorsements in the form of retweets or likes — the dreaded Twitter “ratio” that the heckler was referencing.

“Go back to Davos with the other billionaire elite who think they know how to run the world,” the man at the book launch shouted as private security guards hustled him out of the room and a handful of audience members booed.

A few minutes later, a second heckler spoke up, HuffPost reported.

"Health care is a human right!” the man chanted repeatedly, in apparent reference to Schultz’s claim from the “60 Minutes” interview that “the country cannot afford” to provide free health care for all. He, too, was removed from the event.

The interruptions to Schultz’s first book tour event followed two days of negative backlash online and in print. As The Washington Post’s Michael Scherer reported, Schultz’s announcement on Sunday was met with immediate blowback from Democrats. High-profile liberals, including the singer Cher, threatened to never set foot in a Starbucks again. (Even though Schultz no longer runs the company, he remains one of its largest shareholders.)

“Vanity projects that help destroy democracy are disgusting,” tweeted Neera Tanden, the president of the Center for American Progress and a former campaign adviser to Hillary Clinton and Barack Obama. “If he enters the race, I will start a Starbucks boycott because I’m not giving a penny that will end up in the election coffers of a guy who will help Trump win.”

The pushback continued Monday, with a spate of brutal headlines from newspaper opinion pages that urged Schultz to do anything other than run.

“Just what we need, another ego-crazed billionaire with zero experience in government who thinks he is destined to be president,” wrote Washington Post opinion columnist Eugene Robinson. “What could go wrong?”

Also weighing in was Michael R. Bloomberg, the billionaire former mayor of New York and a potential 2020 Democratic contender, who said in a statement that he had considered running for president as an independent in 2016, but had decided against it because he realized that the country’s electoral college system would put a third-party candidate at a disadvantage that was impossible to overcome.

“In 2020, the great likelihood is that an independent would just split the anti-Trump vote and end up reelecting the President,” he said. “That’s a risk I refused to run in 2016 and we can’t afford to run it now."

Schultz, for his part, doesn’t believe that there’s a real chance of that happening.

“I think lifelong Democrats and many, many more lifelong Republicans than Democrats realize are looking for a home,” he told NPR’s “Morning Edition” on Monday. “If there is a choice between President Trump and a progressive liberal-minded person on the Democratic side, it would kill me to see President Trump be reelected, and I believe that is what would take place.”

While experts disagree on whether a third-party candidate would really have a “spoiler” effect, it appears that Trump believes that to be the case.

“Trump told the crowd at the Trump Hotel tonight fundraiser that he was trying to get Howard Schultz into the race with his tweet earlier today because he thinks he’ll help him, per attendee,” Maggie Haberman, the White House correspondent for the New York Times, tweeted Monday night, referencing the president’s earlier jab that accused Schultz of lacking the guts to run.

At Monday night’s book launch, Schultz said that he would run for president only if he believed he could win, and that he was not “going to do anything to put Donald Trump back into the Oval Office,” the Daily Beast reported. But he also didn’t say whether he would consider dropping out of the race if it appeared that his candidacy was likely to have that result.

Asked about Bloomberg’s contention that it was impossible to get elected as a third-party candidate, Schultz reportedly told the crowd that the former mayor “has built a great business, but I don’t agree with his conclusion.”

Schultz’s political ambitions have apparently angered some reviewers as well. As of early Tuesday morning, his new book, “From the Ground Up: A Journey to Reimagine the Promise of America,” had an average user rating of 1.3, with more than a dozen negative reviews from people who gave no indication of actually having read it. (Amazon founder and chief executive Jeffrey P. Bezos owns The Washington Post.)

“Please stop your vanity campaign,” one typical comment said. “You are endangering the future of our country.”

Among the only dissenting perspectives came from reviewer “Shawn P,” who gave the book five stars. “The book only shipped today, so the reviews are purely political in nature and have nothing to do with the merits of the book," the reviewer wrote. "You’re welcome to your opinions, but being narrow-minded and not listening to what someone has to say says a lot about where we are as a country.”

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