Stumping for Joe Biden wouldn’t take as much finesse. The person who’s spoken with Obama envisioned a similar argument about the existential need to get rid of Trump and reinstate norms, but centered on character. Obama would “elaborate on why [he] chose [Biden] to be his VP in the first place, and how over their eight years in office, he became even more confident that he’d make an outstanding president.”

Read: Waiting for Obama

“He will make it fit whoever it is,” Jarrett said. She added that it’s been gratifying to see nearly every candidate invoke him over the past few months. “It would be political malpractice not to do so,” she said, noting that this speaks to how much potential he has to bring the factions of the party together. (Even Sanders put out an ad on Wednesday morning trying to wrap himself in Obama.)

Obama’s reticence has frustrated many Biden supporters. Some have told me that while they can understand his decision not to fully endorse their candidate, he should have at least done a little buffering about Ukraine: He should have explained that his former vice president was carrying out administration policy, not helping his son Hunter, when he tried to get a government prosecutor there fired.

So Biden supporters were excited that Obama called Biden on Saturday night to congratulate him on his South Carolina win. (Sanders did not get a similar call after he won New Hampshire or Nevada.) This was the second time Obama and Biden spoke last week—Biden had called Obama last Tuesday to talk through ideas ahead of the Charleston debate. But Biden’s campaign is not going to get the endorsement that it’s hoping for. His aides will have to hope that recent endorsements from Obama’s former national security adviser Susan Rice and chief of staff Denis McDonough will be taken as indications of the ex-president’s thinking.

Meanwhile, Obama is still trying to finish his book, which is already about a year behind schedule. He’s digging in on projects such as Higher Ground Productions, the company he and his wife, Michelle, started with Netflix, whose first film won the Oscar for Best Documentary Feature last month. And he put out lists of his favorite books and TV shows of 2019, frustrating those who were hoping he would speak up instead about abuses of power in the Oval Office or migrant children locked in cages.

Obama keeps talking about how Democrats need to move past him, and how voters should pick their leaders instead of the other way around. He muses about his own anti-establishment win in 2008, and how he’d never be where he is now if someone had tried to stop him back then.

“If you’re the product of a process like that, your instinct is not to be the voice from on high,” David Axelrod, Obama’s former strategist, told me. To those who gripe that Obama is underestimating how much influence he could still have, Axelrod said that although he agrees his old boss could make a splash, he questions whether an endorsement would be decisive. “There’s a fair amount of hand-wringing and teeth-gnashing and fear, which to some degree is endemic to the Democratic Party—and some of it is about the various downsides of all of the options—but I’m not sure that someone sweeping in from on high at this point provides that much clarity. It could just as easily divide the party as unify it.”