LAS VEGAS — I knew the win was coming, but I didn’t understand how big it would be. It only really hit me as I walked out of a caucus in the East Las Vegas Community Center where Bernie Sanders had carried all five precincts; in two of those, no other candidate even got enough votes to earn a single delegate.

This was the sort of place where the socialist senator from Vermont had once been expected to founder: It was jammed with Latinos, African Americans, some white gentrifiers — not the stereotypical college students, grooving to whatever hot band was out busking for Bernie last week. I spoke to military wives and service workers, retirees and small business owners — normal people with real jobs. These voters went overwhelmingly for Sanders, as did the rest of the state; with 70 percent of the vote in, Sanders’s support stood at 47 percent, more than 25 points ahead of former vice president Joe Biden’s distant second.

The Nevada results undo all the dire predictions that Sanders’s opponents have (rather hopefully) been making. There’s no obvious cap on Sanders’s support, no suburban or minority firewall that will keep him from winning the nomination. Moreover, the makeup of his supporters suggests all the reasons it is going to be hard for his opponents to unify against Sanders — at least, not fast enough to matter.

I’m not even talking about the racial and gender diversity of his coalition; I’m talking about the way Sanders voters seem to be thinking about the race. They can be broadly divided into three categories: the Realist-Idealists, the Revolutionaries and the Bandwagoners.

The Realist-Idealists are attracted to his far-left position on some issue they care about — usually climate change or Medicare-for-all. Many supported Sanders in 2016. But they are Democrats before they are Sanders voters. They will “Vote Blue No Matter Who” in November, a point they often spontaneously emphasize.

The Revolutionaries, by contrast, resemble the new voters President Trump brought into the GOP. They value authenticity over flexibility; they always tell you that Sanders has been saying the same thing for 40 years. Often they add that 2016 was the first time they got interested in politics or voted.

These folks insist it’s Bernie or Bust. “Any Blue Won’t Do,” said Charlee Magenot, who served as a delegate for Sanders in 2016 and was at a rally for him here Friday.

Even at the expense of keeping Trump in office?

At that point, Magenot’s mother, Debra Cole, interjected. “Donald Trump is not worse, for one reason: He’ll destroy it faster than they will. And then we can rebuild.”

And then there are the Bandwagoners. A few days ago, Tim Miller, veteran of a short-lived Stop Trump PAC, offered a grim warning for Democrats who wanted, say, an actual Democrat to be their nominee. Voters, he noted, like winners; they are inclined to sign on with any candidate who opens up a commanding lead. To stop Sanders, he argued, the other candidates need to attack the front-runner instead of one another, now. They need to think about building a unity ticket, now.

But the Trump equivalent of Bernie’s Revolutionaries are why Republican candidates in 2016 spent months attacking everyone but the front-runner. An early sustained attack might have taken Trump down, but it looked like his ultra-loyal faction would destroy anyone who mounted it. So they tried to knock out everyone else, in the hope that with a larger base, it would be safer to take Trump on.

They failed. As the rest of the Democratic field is failing now. And the Bandwagoners are why.

In East Las Vegas, I spoke to seven Sanders supporters and two undecideds who were considering him. Three out of the nine either said they chose Bernie because he already had so much support — or that they had rejected another candidate for having too little.

Moderate Republicans often claim that Trump is enabling Sanders — that Trump’s unpopularity makes it safer to vote for the socialist. But that’s close to the opposite of what I hear from the voters who are driving his growing margin: Bandwagoners choose Sanders because they think he’s the most electable candidate. After all, his rallies are huge, and his primary margins keep growing.

Maybe those voters are wrong. But if Sanders’s opponents want to stop them from climbing onto the Bernie Bandwagon, they have to build a different wagon — one single wagon, not five — and fill it with enough voters to make it look even more popular than the Berniemobile. That could shift enough Bandwagoners to lure some Realist-Idealists along. If the alternative candidate’s margins are sufficiently overwhelming, even the grumbling Revolutionaries will find it hard to claim they’ve been robbed.

It could work — maybe. But Democrats have to execute this whole maneuver by March 3, Super Tuesday. Because by the end of that day, almost 40 percent of the Democratic delegates will have been allocated. And the Sanders caravan may have enough momentum to cruise all the way to the nomination.

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