As observers continue to try and parse who among President Joe Biden’s closest allies are urging him to stay in the race, signs are pointing to a fractious division between First Lady Jill Biden and Vice President Kamala Harris as the latter prepares for the event that she is asked suddenly lead the ticket.

The Daily Mail reported that a rupture between the two power-hungry boss women kicked into high gear during the 2020 campaign after Harris, then a candidate for president, accused Biden of racism during his 1990s-era push for increased incarceration.

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“Go f*** yourself,” Dr. Biden is reported to have said about Harris to supporters during a private campaign call. It has since only gone downhill, the outlet claims.

One Democratic operative close to the First Lady admitted that her full-throated embrace of a second term in the White House is buoyed in part by her deep-seated animosity toward Harris. The idea that Harris, a former state attorney general who campaigned hard against Biden’s record on race, could suddenly find herself in the Oval Office unnerves her greatly. It’s “One-hundred percent” part of her resistance to Biden dropping out, the source added.

Describing the vitriol over the years, the individual said Dr. Jill claimed to have “hated” Harris during a 2019 feud with then-candidate Biden when she accused him of opposing mandatory racial busing early on as a U.S. senator. “She doesn’t let things go and she has never forgiven Kamala for comments that some took to be allegations of racism,” the person said. When Biden was considering a running mate in 2020, his wife purportedly pushed him toward anyone except Harris.

“Jill was trying to stop Kamala joining the Biden ticket in 2020. She has hated her ever since the school bus thing. But she bit her tongue because Biden boxed himself into a corner by saying he would pick a black woman for his running mate,” another insider told the outlet.

The New York Times reported earlier this week that the White House had clandestinely conducted a poll testing Vice President Harris’s ability to defeat former President Donald Trump in November. The results, while marginally better than Biden’s chances, were not overly encouraging. Still, former colleagues of Harris have rushed to defend the value she brings to the Biden administration. Former Maryland Attorney General and Democrat Doug Gansler told the Daily Mail he finds it “hard to imagine someone more qualified” than Harris and said President Biden “will do the right thing” and step down in the coming days.

Wherever Harris’s relationship stands with the First Lady, Gansler added, “Joe Biden picked her and arguably in some way, he was elected President because he picked her.”

The pressure on Dr. Jill to give up the power grab appears to be adding up. On Thursday she strolled past the press while on the campaign trail for her husband, pausing only after reporters shouted several questions toward her about Biden’s fitness for office and ability to withstand another four years of the world’s most demanding job.

“How are you feeling about the state of the race?” asked a female reporter.

“Why are you screaming at me? You know me. Don’t scream at me. Just let me talk,” said a visibly frustrated first lady before turning around and entering an SUV.

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