Democrats, this is your last chance: You need to stop Bernie Sanders NOW, or he’s going to steal your party out from under you.

In Sunday’s Post, John Podhoretz made the case for why former President Barack Obama could and should speak up, by endorsing his wingman of eight years, Joe Biden, in advance of Super Tuesday.

But while Obama is by far the most consequential voice who could stand up now, every other party leader — starting with House Speaker Nancy Pelosi and Senate Minority Leader Chuck Schumer — shares the same duty to speak out.

When polls close Tuesday, a full 40 percent of the delegates will be set, with most of the rest chosen in the next few weeks. Biden’s win in South Carolina isn’t enough by itself to stop Sanders from romping as the more-moderate vote splits four ways.

Bernie Sanders is not a Democrat, and doesn’t really pretend otherwise: He’s a radical leftist enamored with centralized control of the economy, a man who has romanticized left-wing authoritarianism his entire life.

Democrats believe in more government regulation and intervention then do Republicans. But Sanders goes way beyond that — to government takeover of the economy.

Such extremism is an easy message to sell — especially when no one except the opposition party is willing to call him on it. But Dem leaders — and voters — are fools if they try to out-clever Bernie by quietly working for a brokered convention.

First, because Bernie now has an excellent chance of racking up the delegates for a first-ballot win. Second, because even if he falls short, he could be close enough that it will impossible to deny him — whether or not one of his rivals strikes a deal to put him over the top, say in exchange for the VP slot.

Third, because “robbing” him at the convention is almost as big a gift to President Trump and the Republicans as nominating Sanders in the first place. Either result guarantees that millions of voters who might’ve gone for a Democratic nominee will vote for Trump or a third-party candidate — or just stay home.

Worst of all, there’s the remote chance that Sanders could actually win the White House — which would be a nightmare for the nation and a disaster for the Democratic Party.

Every responsible Democrat knows this is true. Ducking for cover in hopes you can manage the disaster isn’t an answer: Speak up now, or kiss your party good-bye.