Lucas Jackson / Reuters

Throughout the presidential primary, Bernie Sanders promoted his long-held theory of change.

“Real change never takes place from the top on down,” he wrote in his 2016 book, Our Revolution: A Future to Believe In. “It always takes place from the bottom on up. It takes place when ordinary people, by the millions, are prepared to stand up and fight for justice.”

Perhaps so. But his campaign’s claim––that the movement Sanders leads, and only that movement, could propel real change––was all but refuted yesterday when Sanders lost primaries in Mississippi, Idaho, Missouri, and Michigan despite a field cleared of all contenders for the nomination save Joe Biden. (North Dakota and Washington State remain too close to call.) The results, together with Sanders’s unexpectedly weak showing last week on Super Tuesday, suggest that the democratic-socialist candidate lacks the support he’d need to secure the Democratic nomination.

Turnout surged, but Sanders still didn’t have the votes. And if he ekes out an improbable victory over Biden and beats Donald Trump? Even then, the primaries to date suggest that he would command insufficient support to pass the agenda that he himself describes as a political revolution.

Like Barack Obama, Sanders would face an uphill battle to enact his legislative agenda, dividing Democrats and facing nearly united opposition from Republicans. Yet the Sanders coalition appears to be less numerous and less diverse than the Obama coalition; there is no reason to think it would achieve more.

If Sanders were younger, his success among 18-to-29-year-old voters, a cohort he won by 58 percent in Michigan, might bode well for his political future. But he is 78 years old. Campaigning for president at 82 after losing in successive primary cycles seems unlikely. It will be interesting to see which candidates Sanders voters support in future Democratic primaries. How many are most attached to Sanders himself? How many are loyal to democratic socialism? How many would be attracted to an honest-seeming populist who campaigned against the establishment with a different ideology?

Democratic socialists may one day marshal bottom-up pressure to pass parts of the Sanders agenda. But after yesterday, the chance that Sanders himself will sign their bills into law is vanishingly small. He’s led their movement more successfully than anyone would have imagined circa 2015. Come 2021, the movement may need to find a new leader to secure its future.

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