The socialist emperor of Vermont has no clothes.

The feverish anti-establishment antipathy that’s helped fuel Bernie Sanders’ presidential ambitions over the past few years has relied on a belief that the system (what system? every system) has been rigged against him.

From Wall Street to drug companies, from the Democratic Party to corporate America, these powerful institutions were aligning to rob him of what was rightfully his, what “the people” wanted.

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President Trump, sensing a kindred spirit, helped promote this conspiracy theory on Sanders’ behalf, telling anyone who would listen, “I think it’s rigged against Bernie…It was rigged against me.”

Republicans have also been happy to sing this tune, with the head of the Republican National Committee, Ronna McDaniel, recently insisting Democrats were heading for a “brokered convention, which will be rigged against Bernie if those superdelegates have their way on that second vote.”

Sanders himself rang the alarms this week about the coming coup: “Look, it’s no secret,” he told reporters. “The Washington Post has 16 articles a day on this — there’s a massive effort to stop Bernie Sanders...The corporate establishment is coming together, the political establishment is coming together, and they will do anything and everything.” That, presumably, gets his supporters riled up and ready for battle, and there’s likely some truth to the idea that mainstream Democrats are concerned Sanders’ socialism will get Trump reelected. (They’re not wrong.)

But what happened on Super Tuesday totally dismantled the Sanders conspiracy theory that, if only “the establishment” would get out of voters’ way, this would be his for the taking.

Joe Biden surprised even the establishment political class with his 10-state win on Tuesday night, after months of defending the health of his candidacy.

The bounce he got from South Carolina’s win on Saturday, coupled with well-timed endorsements in key states, gave voters all over the country and over diverse demographics permission to cast their votes for a guy who finally proved he can win.

Sanders can’t blame the establishment for voters taking to the polls, which is what happened in South Carolina. He especially can’t blame the establishment for voters turning out for his opponent in states where Biden barely campaigned, states like Massachusetts and Minnesota. Or delegate-rich Texas, where Biden had not figured to play, accounting for what Politico called his “11th-hour, shoestring operation in the state.”

The Sanders campaign itself criticized Biden’s lack of attention to Texas just before he won it. “You can’t show up in our community at the last minute and think you’re going to get elected off of name ID,” said Chuck Rocha, a senior adviser to Sanders. “You’ve got to invest in the community — that’s why we have spent the second-most amount of money talking to Latinos in that state behind billionaire Michael Bloomberg.”

And yet, it still couldn’t buy the state for Sanders.

Conversely, Biden’s campaign was going broke. The establishment had nothing to do with that. Bloomberg spent $43 million on ad buys in Virginia, North Carolina and Alabama; Biden spent just $772,000, and still he won all three.

The establishment had nothing to do with Sanders’ failure to win important endorsements, including from his own people like Nevada’s Culinary Union and the Chicago Teachers Union.

The establishment isn’t responsible for Sen. Elizabeth Warren, Sanders’ main progressive competitor, staying in the race as long as she has, siphoning off votes from him.

The truth is, despite having run once before, accruing potent name ID and running a sophisticated grassroots campaign, Sanders is simply not a national candidate. He has a vocal, very aggressive base of support, but it’s localized and it’s not representative of a majority of Democratic voters. His candidacy has a very real ceiling, and Biden just found it.

The truth is the establishment isn’t standing in Sanders’ way. Voters are.

The only question now is, how will Sanders’ repeated conspiracy theories about the establishment coup go over now that that ruse has been thoroughly unmasked?

S.E. Cupp is the host of “S.E. Cupp Unfiltered” on CNN.

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