In voting for Bernie Sanders in the Nevada caucuses over the weekend, significant numbers of people registered their disenchantment with establishment politics and economics. Though it wasn’t enough to put him over the top as it did in New Hampshire, with slightly over 47 percent of the vote, Bernie did better than many expected.  If anyone thought he would leave for South Carolina with his tail between his legs, they were mistaken.

“We have come a very long way in nine months,” Sanders said in his concession speech. “The wind is at our backs. We have the momentum. And I believe that when Democrats assemble in Philadelphia in July at that convention, we are going to see the results of one of the great political upsets in the history of the United States.”

Meanwhile, the Clinton team dodged its worst nightmare – a last minute Sanders’ surge that would put him over the top – and they could even point to a substantial win for their side. It wasn’t a landslide victory, but they never thought it would be. The early polls that had Hillary winning by a large margin were never a good predictor, since at that time, most voters didn’t know Sanders and what he stood for. By last weekend they did.

What is impressive about Hillary’s Nevada win, however, was the broadly-based coalition that supported her. It included most of the main categories of voters that are crucial to winning the nomination and then making a successful presidential run. Missing, and glaringly so, were young voters. Bernie’s campaign has become the place where they expend their energy and cast their votes. In their eyes, he is the genuine article, and an alternative to poll- and money-driven politics.

But Bernie has yet to demonstrate that he can assemble the kind of expansive coalition that Hillary has. And that is something that he must do, and quickly, as the primary season heads to the South and Midwest. More to the point, he has to win the support of significant sections of African American, women, and more moderate voters in the delegate-rich primaries on March 1 and 15. If he doesn’t, the likelihood of “one of the great political upsets” becomes very slim.

In any event, the campaign – and it will likely go all the way to the convention – has already revealed that a big space exists for progressive and left politics if they are framed in broad, popular, and non-sectarian ways. I have heard a few people say that Bernie’s isn’t socialist enough, but I would say that his pitch is just about perfect, socialistically speaking.