CNN  — 

Faced with slumping poll numbers and struggling to raise money, Joe Biden is pulling out his trump – ahem – card against front-runner Elizabeth Warren: He’s painting her as an out-of-touch elitist.

At virtually every public – and private – event Biden has held over the last week (or so) of the campaign, he has bashed Warren for what the former vice president believes to be her condescension to pragmatic Democrats like him.

He even wrote a Medium post about it! Here’s the key bit:

“If someone doesn’t agree with you — it’s not just that you disagree — that person must be a coward or corrupt or a small thinker.

“Some call it the ‘my way or the highway’ approach to politics. But it’s worse than that. It’s condescending to the millions of Democrats who have a different view.

“It’s representative of an elitism that working and middle class people do not share: ‘We know best; you know nothing’. ‘If you were only as smart as I am you would agree with me.’

“This is no way to get anything done. This is no way to bring the country together. This is no way for this party to beat Donald Trump.”

Strong stuff, right?

Let’s trace this back to the root. It all began when Warren released her detailed plan on how she would pay for “Medicare for All,” a proposal that would eliminate all private insurance in favor of a single government-run plan. Biden and his team criticized that plan as filled with pie-in-the-sky calculations and fuzzy math. To which Warren said this:

“So if Joe Biden doesn’t like that, I’m just not sure where he’s going. Democrats are not gonna win by repeating Republican talking points and by dusting off the points of view. … But if anyone wants to defend keeping those high profits for insurance companies and those high profits for drug companies, and not making the top 1% pay a fair share in taxes, and not making corporations pay a fair share in taxes, then I think they’re running in the wrong presidential primary.”

Biden seized on those comments – partly out of, I think, personal pique and partly out of political strategy – and has spent every day since Warren made them attacking her for them.

“It’s just an elitist attitude that it’s either my way or the highway,” he said in a recent radio interview.

This attack is interesting – and potentially telling – on a variety of levels.

Most importantly, it appears to be a near-certain predictor of how President Trump will attack Warren if and when she becomes the Democratic nominee.

While Trump has spent most of his time hitting Warren for her claims of Native American heritage, it seems very likely that the President would turn to her work as a Harvard professor and her policy proposals – especially “Medicare for All” – to cast her as just another coastal liberal elitist trying to tell you, average Joe, how to live your life and what to believe.

(Worth noting: Warren grew up in Oklahoma, not at Harvard.)

That likelihood puts a premium on Warren’s response to Biden’s attacks – particularly given that all of this comes even as establishment figures within the party are increasingly worried that Warren, as the nominee, is too liberal and too easily caricatured by the President, and nominating her could cost the party its best chance of winning the White House.

In an interview with CNN’s Dana Bash on Thursday, Rep. Gerry Connolly of Virginia spoke to this unease regarding Warren and her health care funding plan. “I think Democrats threaten that insurance at their own peril,” he said. “We are on a winning streak. We’ve got to be very careful not to upset that.”

To date, Warren has largely ignored the “elitist” attack from Biden. In an interview at North Carolina A&T University on Thursday, Warren pushed back more generally against critiques that her “Medicare for All” plan wouldn’t pass Congress by saying that “you don’t get what you don’t fight for.”

Which is very on brand for her. The fighter with a plan and all that. But ignoring this Biden attack won’t make it go away. And Biden, backed into a corner of sorts in the race, seems very unlikely to simply abandon the attack now.

Warren needs a good answer – maybe one rooted in her humble upbringing on the “ragged edge of the middle class” – to prove to Democrats that she can knock this hit down, both now and when it inevitably comes from Trump.