The idea of raising taxes on the rich, particularly after President Donald Trump and the GOP-controlled Congress cut taxes for corporations and individuals, including the wealthy, in 2017, is quickly emerging as one of the most crucial topics of the 2020 campaign. Sen. Elizabeth Warren of Massachusetts, who is exploring a run for president, has proposed a wealth tax on Americans with more than $50 million in assets .

However, polls have shown that voters generally approve of the idea of taxing the wealthy at a higher rate. Indeed, a recent Hill-HarrisX survey of 1,001 registered voters found that 59 percent supported Ocasio-Cortez's proposal . A Fox News poll published last week found that 70 percent of registered voters backed hiking taxes for families making more than $10 million a year.

"I respect the Democratic Party. I no longer feel affiliated because I don't know their views represent the majority of Americans. I don't think we want a 70 percent income tax in America," Schultz told CNBC's Andrew Ross Sorkin in New York.

In an interview Monday night, he cited her idea as one of the reasons he could never run for president as a Democrat. Schultz believes the party has moved too far left, and he doesn't believe in their tax and spending priorities.

Billionaire former Starbucks CEO Howard Schultz is no fan of Rep. Alexandria Ocasio-Cortez's proposal to slap a 70 percent marginal tax rate on income above $10 million.

Schultz's veiled criticism of Democratic socialist Ocasio-Cortez's idea to tax earnings over $10 million at 70 percent matched the concerns of many of the uber-rich who attended the World Economic Forum in Davos, Switzerland, last week. The billionaire elite expressed dismay at the direction the 29-year-old freshman firebrand from New York wants to take the nation.

Earlier this month, Ocasio-Cortez told CBS' "60 Minutes" that a wealth tax could help pay for a "Green New Deal" that would transition the U.S. away from fossil fuels.

In a "60 Minutes" interview that aired Sunday, Schultz, who built Starbucks into a global powerhouse during two tenures as chairman and CEO, said he's "seriously thinking" of running for president "as a centrist independent, outside of the two-party system."

"The way I've come to this decision is, I believe that if I ran as a Democrat, I would have to say things that I know in my heart I do not believe, and I would have to be disingenuous," Schultz, a lifelong Democrat until now, further explained to Sorkin.

Schultz said the nation cannot afford the priorities of far-left Democrats, including full government-paid health insurance and college tuition. "We are sitting right now with a national debt of $21.5 trillion on the balance sheet of our country," he said. "And if we were a company, if America was a company, at $21.5 trillion of debt, adding $1 trillion a year, we would be facing insolvency."

The possibility of Schultz running as an independent has struck fear in the hearts of Democrats. A strong third-party candidacy from Schultz, provided he didn't win, could act as a spoiler for Democrats, taking votes away from their nominee and leaving the White House in the hands of Trump or another Republican. Some voices on the left, including in the wealthy donor class, called for boycotting Starbucks to protest a Schultz candidacy.

Democrats want to avoid a situation like businessman Ross Perot's third-party run in 1992. Perot won nearly 19 percent of the popular vote in the three-way race against GOP incumbent President George H.W. Bush and Democratic challenger Bill Clinton. The enthusiasm around Perot was blamed for giving the presidency to Clinton.

Trump himself weighed in on Schultz's flirtation with presidential politics. In a tweet Monday, Trump said Schultz "doesn't have the 'guts' to run for President!"

Schultz on Monday evening tried to reassure concerned Democrats, however: "I certainly am not going to do anything to put Donald Trump back in the Oval Office."

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