Former U.S. Labor Secretary Robert Reich released a video Tuesday explaining his case for why Sens. Bernie Sanders or Elizabeth Warren pose a far better chance of defeating President Donald Trump in 2020 than "some billionaire-backed milquetoast moderate."

"These two have most of the grassroots energy, most of the enthusiasm, and most of the ideas that are critical for winning in 2020," said Reich, a professor at the University of California, Berkeley.

"Most importantly, both Warren and Sanders understand that our system is rigged and that economic and political power must be reallocated from a corporate Wall Street elite to the vast majority," Reich added. "This is why both Warren and Sanders are hated by the corporate Wall Street wing of the Democratic Party."

Calling the notion that Sanders and Warren are too far to the left "total rubbish," Reich said the progressive senators stand the best chance to beat Trump in the general election.

Nominating a moderate like former Vice President Joe Biden or South Bend, Indiana Mayor Pete Buttigieg, Reich argued, "will increase the odds Trump gets a second term."

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