brain cancer, bounced back from a broken hip and outlived his political adversaries. And now he is setting a record for presidential durability that may be hard to break.

Though frail and generally confined to his modest ranch house in Plains, Georgia, Carter has not only refused to surrender to the inevitability of time, but he has also perked up in recent months, according to family members. He has become a little more engaged again, telling his children and grandchildren that he has a new milestone he wants to reach — not his birthday, which he professes not to care that much about, but Election Day, so that he can vote for Vice President Kamala Harris.

“It’s a gift,” Josh Carter, one of his grandsons, said of the past few months. “It’s a gift that I didn’t know we were going to get.”

Jimmy Carter had already surpassed all of his predecessors to become the longest-living president, but some of those who have experienced his stubborn irascibility over the decades said they were not surprised that he is approaching his second century.

“That’s Jimmy,” said Gerald Rafshoon, his White House communications director and longtime friend. “It’s almost like his whole life has been to go against the norm. Tell him he can’t do something, just tell him that, and you’re bound to see the determination.”

Jimmy Carter’s hometown, Plains, the blink-and-you’ll-miss-it speck on the map in southwest Georgia with barely 500 residents, is celebrating his birthday with a flyover of military jets, a naturalization ceremony for 100 new citizens and a concert. Supporters already held a lively concert this month at Atlanta’s Fox Theatre to be televised today, including performances by the B-52s, BeBe Winans and others, along with videotaped tributes from most of the other presidents.

Jimmy Carter was not able to attend personally. He has become severely diminished physically. There are days when his grandchildren and great-grandchildren travel to Plains only to be told he is not able to see them.

The death last year of his wife, former first lady Rosalynn Carter, was crushing and disorienting, relatives said. After 77 years of marriage, many around him assumed he would follow her soon.

“When she passed, we all frankly thought that he wouldn’t be much longer,” said Jason Carter, another grandson and the board chair of the Carter Center, the philanthropic institution founded by the former president and first lady. “And I think he had a real low period for a while. But these last few months, he’s really gotten reengaged with the world.”

The former president listens to music, including old standbys like Bob Dylan and the Allman Brothers Band. His favorite song is Garth Brooks’ “Unanswered Prayers.” He inquires about the work being done at the Carter Center and shares his opinions about the state of the Atlanta Braves. Ronald Acuña Jr.’s season-ending knee injury was a source of frustration.

He has followed the presidential election. He considers President Joe Biden a friend as well as a political ally, remembering how Biden as a young senator from Delaware had been among the earliest national Democrats to endorse his 1976 presidential candidacy.

Biden’s decision to end his reelection bid in July engendered a measure of pride and respect from Jimmy Carter, Jason Carter said. The former president’s work with election monitoring and nurturing democracies had taught him how rare it was for a leader to choose to surrender power for the sake of his party and his country.

“That’s a big — historically big — deal,” Jason Carter said. “Just like the rest of us, he couldn’t believe what we were watching, because it was so unprecedented, and I think that was really affecting for him as well.”

The Carter family’s support of Harris stems, in part, from its staunch disapproval of former President Donald Trump. Trump has “a meanness and a darkness” that the family views as the antithesis of Jimmy Carter’s philosophy, Jason Carter said.

Not surprisingly, Trump was the only president not asked to send a video tribute to the Atlanta concert. The Republican presidential nominee used Jimmy Carter as a punch line on the campaign trail to mock Biden before the incumbent president left the race. “He makes Jimmy Carter look like a genius by comparison,” Trump said at one rally last summer.

Of course, Trump makes Jimmy Carter look popular by comparison. In a Gallup poll last year, 57% of Americans retrospectively approved of Jimmy Carter’s presidency compared with only 46% who approved of Trump’s.

In part, that may stem from the revisionist wave of nostalgia since Jimmy Carter went into hospice. Once seen as a failed president who lost reelection only to become a globally admired humanitarian after leaving the White House, he has benefited from a reevaluation in the last 19 months.

“He’s already a part of history and so many people who are getting to know him now don’t remember his presidency,” said E. Stanly Godbold Jr., author of a two-volume biography of Jimmy and Rosalynn Carter. “And that might be a good thing. They may have a more detached view.”

In the weeks since Biden’s withdrawal, Jimmy Carter has grown particularly enthusiastic about Democratic presidential nominee Harris, who has called multiple times to check in on the former president, particularly after his wife’s death.

“She’s not getting a supporter out of that — she’s got our support,” Jason Carter said. “But I think there was just a real personal kinship there. I think my grandfather is obviously compelled by her story as a real example of the American dream.”

As he reached his 80s and 90s, Jimmy Carter became defined by his vigor and his defiance of the toll of aging. He published a memoir at age 90 and only moderately reduced his role at the Carter Center. He continued teaching at Emory University in Atlanta and routinely taught Sunday school at Maranatha Baptist Church in Plains.

At the Atlanta concert celebration this month, Monica Pearson, a longtime television news anchor in Atlanta, recalled once telling him that “90 is the new 60 — and I was absolutely right!”

Eventually, though, that resolve to keep active could look to family and caretakers an awful lot like stubbornness, showing up to teach Sunday school when everyone advised against it or helping build houses with Habitat for Humanity while bruised and bloodied after a fall.

Shortly before Jimmy Carter was scheduled to appear in 2019 for what was then his annual stint building houses for the disadvantaged, Jonathan T.M. Reckford, the chief executive of Habitat for Humanity International, heard on the news that the former president was in the hospital. “I was just panicked,” Reckford recalled. “Then I quickly got a call from him, a little bit grumpy. ‘I’m fine. I’ll see you there.’ And he shows up with a black eye and a big bandage around his head.

“It really epitomized who he is,” Reckford added. “There are people who come out for the photo ops, and that is so not President Carter.”

Other volunteers used to ask to be put on the house Jimmy Carter was working on, but Reckford would warn that it was not for the faint of heart. “It’s not a competition — as long as President Carter’s house gets finished first,” he said. “You don’t want that submarine commander’s glint that you’re not working hard enough.”

The country witnessed that gritty defiance of limitations in November when Jimmy Carter emerged from hospice care and traveled to Atlanta for his wife’s memorial service.

“I don’t know what keeps him going,” Jason Carter said. “I think he doesn’t know how to give up on anything.” But he added that he worried that his bed-bound grandfather was no longer having new experiences. “He’s so physically diminished,” he said. “I just worry that he’s not enjoying himself.”

Josh Carter said that when he visits, he is not seeing a president or an acclaimed humanitarian. “When I go back to Plains, he’s my grandfather,” Josh Carter said — the same one who took him into his wood shop and instilled in him a passion for woodworking.

The former president gave Josh Carter everything in his wood shop on two conditions: that he use it, and that he start using it right away, not wait until after his grandfather’s death. He complied, employing his grandfather’s tools to build a cabinet celebrating his grandparents’ 75th wedding anniversary.

Jimmy Carter’s children and their spouses — including his sons Jeff and Chip and daughter Amy — have been the most directly involved in his care and send reports on his condition to the broader family.

“The caregiving side of this takes a toll, as it would in any family,” Jason Carter said. “All of us, I think, are surprised to see that he’s still going.

“You know,” he added, “he may very well be immortal.”