RealClearPolitics founder Tom Bevan said on the "Fox News Rundown" podcast that Democrats are "petrified" of Sen. Bernie Sanders becoming the nominee, and warned of a "nightmare scenario for Democrats" heading into Super Tuesday.

"I mean, there's still a lot of scenarios that you can craft about this race," he said Monday. "Maybe Bernie comes out, but he's not so far ahead. And I think in some ways, that's almost the nightmare scenario for Democrats because then it will be there will still be this urge and push by the Democratic establishment to try and take this thing away from Bernie if he's not far enough out in front."

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Bevan said that the race could get "really, really ugly and go on a long time" if remaining candidates Joe Biden, Michael Bloomberg and Elizabeth Warren emerge with a split delegate count.

"Honestly" he added, "I know the Democratic establishment is petrified of Bernie as the nominee and wants to do anything just to stop him."

Bevan also noted that while early voting does serve as a good indication of the nominee, “there is still a slice of the electorate…who typically don’t make up their mind until the final week or final days.”

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"A lot of folks had already made up their mind ahead of time and are locked in," but "there is still a slice of the electorate, small, true independents who are out there who typically don't make up their mind until the final week or final days," Bevan explained.

He added, "If it is a close election in these swing states, that will be decided by a few thousand votes and in some of these states, that could be critical."

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