Democratic leaders went into damage-control mode Wednesday, insisting the party won’t be splintered by Bernie Sanders’ relentless leftist campaign against Hillary Clinton.

A day after Sanders trounced Clinton in the West Virginia presidential primary, Democratic National Committee Chair Debbie Wasserman Schultz tried to shift the focus to divisions among Republicans and Donald Trump.

But reporters weren’t buying the spin — peppering her with questions in a telephone press conference about the harsh tone of the Democratic contest, potential unrest at the party’s July convention, and Sanders’ complaints that the platform committees are rigged against him.

Wasserman Schultz said Sanders “misunderstood” the rules and noted most of the convention committee members will be chosen proportionally based on the delegates amassed by the candidates, not by party brass.

Sanders wants the party to adopt his agenda, which includes higher taxes on the rich.

Wasserman Schultz noted that the tone of any campaign gets nastiest toward the end.

“You will have pointed language. I advised the candidates and supporters to be mindful of the language,” she said. “We have passionate people on both sides. We don’t want to make it harder to reunify.”

That may be difficult. Sanders’ campaign manager, Jeff Weaver, on Wednesday predicted a “disaster” if Clinton is nominated.

“Our mission is to win as many pledged delegates as we can between now and June 14,” he said in a fundraising email, according to the Washington Times.

‘In every state that we have won, in 19 states, we have had to take on the entire Democratic establishment … so please do not moan to me about Hillary Clinton’s problems.’ - Bernie Sanders

“Then we’re going to have a contested convention where the Democratic Party must decide if they want the candidate with the momentum who is best positioned to beat [Donald] Trump, or if they are willing to roll the dice and court disaster simply to protect the status quo.”

Some of Sanders’ staffers and volunteers have even drawn up a plan for the Vermont senator to hold an alternate “convention” if he fails to win the nomination, Politico reported Wednesday night. The early draft notes, however, that Sanders’ ultimate goal would be to defeat Trump at all costs.

Meanwhile, Sanders chafed at a question about Clinton facing attacks from both him and Trump.

“Oh, really? . . . In every state that we have won, in 19 states, we have had to take on the entire Democratic establishment. We have had to take on senators and governors and mayors and members of Congress, so please do not moan to me about Hillary Clinton’s problems,” Sanders said in an MSNBC interview.

A DNC source said preliminary back-channel discussions are under way to make sure Sanders is taken care of — if he quickly backs Clinton when the primary season ends.

“He will give a good floor speech and some wording will be changed in the platform [to accommodate Sanders],” the insider predicted.

And New York Sen. Charles Schumer, the next likely minority leader, will make sure that Sanders gets a hero’s return to the Senate, sources said.