The 2020 Democratic field is running hard to the left as the Democratic Party celebrates socialism. But several of the candidates can well afford taking down capitalism at this point, because they're already multimillionaires and have incomes in the top 1 percent.

Former Reps. Beto O’Rourke and John Delaney, Sen. Elizabeth Warren, and former Colorado Gov. John Hickenlooper are among the wealthiest Democratic presidential candidates. Other hopefuls have earned hundreds of thousands of dollars in book royalties and speaking fees.

OpenSecrets.org estimates that O’Rourke was worth around $9 million in 2015. His 2017 House financial disclosure form shows assets ranging from $3.6 million to $16.6 million and liabilities ranging from $1.3 million to $5.8 million.

The former Texas representative co-founded an El Paso web and software company in the late '90s, but much of his wealth comes from his wife Amy O'Rourke. She is the daughter of real estate tycoon Bill Sanders, who Forbes estimated is worth around $500 million.

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Warren, who proposed a wealth tax on households worth more than $50 million, reported in a Federal Election Commission financial disclosure filing that she and her husband have investment accounts and other financial assets worth between $4 million and $11 million. That doesn’t include her three-story Victorian home in Cambridge, Mass., valued at nearly $2 million in 2015.

Warren reported no debts, and in 2017 also received nearly $400,000 in royalties for her book, This Fight Is Our Fight, her Senate financial disclosure showed.

Congressional rules prohibit members from accepting speaking honorariums and other types of outside income, but those with star power can supplement their $174,000 annual Congressional salary with hundreds of thousands of dollars from book royalties.

Sen. Bernie Sanders, I-Vt., a self-described socialist, made more than $880,000 in book royalties and advances in 2017, his Senate financial disclosure revealed. He also owns three homes: a house in Burlington, Vt., a Washington, D.C., townhouse, and a $575,000 vacation lake home in Vermont that his family bought with cash in 2016.

Sen. Cory Booker, D-N.J., in 2017 got a $325,000 advance for his book, United: Thoughts on Finding Common Ground and Advancing the Common Good. He also reported between $600,000 and $1.3 million in assets and no liabilities in his 2017 financial disclosure.

Booker’s, Warren’s, and Sanders’ book advances combined with their congressional salaries likely put them in the top 1 percent of income earners: A 2018 analysis of wages by the Economic Policy Institute found that a family needed an annual income of $421,926 in 2015 to be in the top 1 percent. The average income of the top 1 percent was $1.3 million.

Delaney and Hickenlooper, two long-shot candidates, are both self-made millionaires.

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A February 2018 analysis of Delaney’s financial disclosure form put his net worth at $92.6 million, making him the 6th richest member of the 115th Congress. OpenSecrets.org estimated that his net worth was $233 million in 2015.

The former Maryland representative co-founded two financial companies, Health Care Financial Partners and CapitalSource, that provided loans to other businesses. Both were publicly traded, and Delaney was at one time the youngest CEO of a company traded on the New York Stock Exchange. He embraced capitalism and scorned socialism in a recent Fox News interview.

Hickenlooper became a millionaire by opening restaurants and breweries. While running for governor in 2010, Hickenlooper released 23 years of his tax returns, which that showed he had earned more than $16 million since 1985.

Despite being a successful entrepreneur, Hickenlooper hesitated to call himself a capitalist in a recent CBS interview.

“I think it’s kind of a silly question,” Hickenlooper said when asked if he is a capitalist or a socialist.

Former Vice President Joe Biden, who has not yet announced a 2020 presidential bid but leads in early Democratic primary polls, wrote in his book Promise Me, Dad that President Barack Obama joked in 2008 about Biden's financial situation.

“That was one of the easiest vets in the world. You own nothing,” Biden reported Obama as saying. OpenSecrets.org estimated Biden’s net worth to be minus $947,987 in 2014.

Since leaving office, however, Biden has made a killing in speaking fees. For example, he got $200,000 last year from the Economic Club of Southwestern Michigan, the New York Times reported, and $150,000 for a January appearance at the Broward Center in Florida.

Biden and his wife in 2017 bought a $2.7 million vacation home in Rehoboth Beach, Del., shortly after they signed a multibook deal reportedly worth $8 million. He owns another home in Wilmington, Del., now worth about $1.9 million.

Campaigns and representatives for O’Rourke, Delaney, Harris, Booker, Sanders, Hickenlooper, and Biden did not respond to requests for comment.