Joe Biden’s barely veiled attack on the “elitism” of an unnamed Democratic opponent (but clearly Elizabeth Warren) on Tuesday night escalated the growing rift between the two candidates, but if the dig seems familiar, it’s because it’s been used before.

By Republicans.

While Warren’s name never made it into the former vice president’s newest Medium post, it begins with a reference to a comment the Massachusetts senator made that he was “running in the wrong presidential primary." While Warren also did not mention Biden’s name, it was equally clear who she was referencing.

The post was published in an apparent effort to hit back at Warren in similar MadLibs fashion. But in incorporating the word “elitism,” Biden waded into Republican talking point territory.

“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,’” Biden wrote five paragraphs into his lengthy statement, all-but referencing Warren’s recent comments suggesting that he might not belong in the Democratic primary for pushing a more moderate plan than Medicare for All.

By Wednesday morning, Biden decided to fill in the blanks.

“If you don’t agree with Elizabeth Warren, you must somehow be not a Democrat. You must somehow be corrupt. You must somehow not be as smart as she is,” Biden said to Joe Madison on SiriusXM’s Urban View program. “It’s just something we don’t do in our party. It’s not who we are.

“She has things in her plan that are just not realistic, but if you question it, she says you don’t understand or you’re talking like a Republican,” he went on. “It’s just an elitist attitude that it’s either my way or the highway.”

Allies in Trump’s circle and the Republican Party have said privately for months that they view Warren as elitist and intend to add that branding to their arsenal of attacks. And with the general election now less than one year out, those attacks could take on a new relevancy when promoted by Biden, one of the Democratic Party’s own leading presidential candidates.

"Warren's time as a corporate legal consultant and Harvard professor were bound to become fodder in this election,” one GOP operative told The Daily Beast. “Having Democrats start to define her as misleading and inauthentic only helps President Trump's ability to provide a clear contrast if she makes it to the general."

Conservative host Rush Limbaugh, a close ally of Trump, recently pushed the same line of critique on his “Morning Update” program. Last week, Limbaugh said that “the reason most voters will avoid Elizabeth Warren at all costs is because we’ve seen her and the elite in action.” As he went on, the rest of his statement offered a striking similarity to Biden’s own written comments dismissing the mentality that ‘If you were only as smart as I am you would agree with me,” which he wrote online on Tuesday night.

“We have learned they aren’t smarter than we are,” Limbaugh said.

The branding is not new. Scott Brown, the former Massachusetts senator who Warren bested in her 2012 Senate race, criticized her “elitist attitude.” Warren, a former Harvard Law School professor who created the Consumer Financial Protection Bureau, beat Brown by more than seven points. In his SiriusXM appearance on Wednesday, Biden used that exact phrase.

Biden’s decision to adopt the line comes less than three months before the Iowa caucus, a contest in which polling shows the 2020 race tightening between them. New surveys released on Monday by The New York Times Upshot and Siena College shows Warren does worse than Biden with registered voters in several critical battlegrounds, including in the Midwest. In Michigan, Biden earned 44 percent of support while Warren had 39 percent. In Iowa, Biden's support came in at 44 percent, while Warren’s was at 40 percent. In Florida, Biden got 46 percent, compared to Warren’s 41 percent.

“People don’t like Harvard professors,” a well-placed Republican Senate aide said. “It would be malpractice not to start tagging her as elite.”

Warren has taken steps to distance herself from that perception, regularly talking up her humble roots on the campaign trail and swearing off big dollar fundraisers and corporate donations. In the third fundraising quarter, she brought in $24.6 million, in part due to her grassroots campaign’s ability to generate recurring small-dollar donations. She often talks about having a plan to fix Washington’s corruption and taxing wealthy individuals.

But during a fundraiser in Pittsburgh on Tuesday night, Biden, whose campaign is now receiving the financial assistance of a super PAC, took a more direct jab at Warren, highlighting her past voting history as a Republican.

“This person has only fairly recently in the mid-90s become a Democrat,” according to a pool report of the event.

His moves come at a particularly trying week for Democrats, with the two frontrunners escalating a one-on-one fight over the merits of the progressive Medicare for All proposal—a plan House Speaker Nancy Pelosi reiterated her concerns about in recent days—versus the Affordable Care Act, one of former President Barack Obama’s signature accomplishments, which Biden has campaigned heavily on over the past several weeks.

A spokesperson from Warren’s campaign declined to comment.

Biden’s rapid response director Andrew Bates told The Daily Beast, “Joe Biden is running to rebuild the American middle class and ensure that everyone is in on the deal this time, and he's proud of the diverse coalition of working people who have supported him since he launched his campaign."

Still, not every Republican is convinced the attack will stick.

Barry Bennett, a former senior adviser to the 2016 Trump campaign, told The Daily Beast that’s not the preferred label he would use for Warren.

“I’m just going to call her a lying socialist,” he said.