For indispensable reporting on the coronavirus crisis, the election, and more, subscribe to the Mother Jones Daily newsletter.

On Wednesday, the Bernie Sanders campaign released three new advertisements aimed at voters in the six states casting their primary ballots next week. And one of them touts Sanders’ relationship with President Barack Obama, an eyebrow-raising assertion for a candidate who had stood out among elected officials one of the 44th president’s fiercest left-leaning critics.

This ad, titled, “Feel the Bern,” layers audio narration from Obama over campaign images and archival footage of the Vermont senator’s appearances alongside the 44th president. The voice-over lavishes 30 seconds of Sanders praise from Obama, noting he has “great authenticity, great passion, and is fearless.” Obama also says Sanders “got bills done” from his perch on the Senate Veterans’ Affairs committee, countering an attack advanced by Sanders’ detractors that the senator, by virtue of his stubborn commitment to liberal ideals, has failed to compromise or get legislative results.

The audio is not something Obama recorded for the campaign, and rather comes in part from a 2016 Politico interview Obama did about his potential successors, a conversation in which the president heaped praise on both Sanders and his opponent that year, Hillary Clinton. The advertisement’s first line, “Bernie is somebody who […] has the virtue of saying exactly what he believes, and great authenticity, great passion, and is fearless,” omits a clause from the original soundbite in which Obama admits that Sanders is someone “I don’t know as well because he wasn’t, obviously, in my administration.”

Another clip comes from Obama’s 2016 Democratic National Convention speech, when he was pushing party unity and lauding the organizing fervor Sanders’ supporters had brought to the primary campaign.

Sanders is just the most recent Democratic 2020 hopeful to lean on the sky-high popularity of the 44th president among Democrats to make a case to voters. Former New York mayor Michael Bloomberg put his own spliced cut of Obama praise on airwaves last month. Meanwhile, Joe Biden has premised his entire campaign on the “Obama-Biden” administration and has the ads to match.

But Sanders’ take is perhaps the most conspicuous: Sanders had been, among liberal federal lawmakers, one of Obama’s most vocal critics. The Atlantic reported last month that the Vermont senator had contemplated mounting a primary challenge against Obama during the 2012 election cycle.

And Obama returned the skepticism in kind. He’s taken pains to remain publicly throughout the primary, but reportedly once said in private that he would step in to stop a Sanders nomination if it looked likely.

Listen to MoJoreporters Tim Murphy and Fernanda Echarvarri explain Biden’s big night, Bernie’s long fight, and the knockdown fight for delegates to come, on this special Super Tuesday edition of the Mother Jones Podcast:

Listen to the latest episode of the Mother Jones Podcast: Subscribe using Apple Podcasts, Spotify, Stitcher, or your favorite podcast app.