CHICAGO — Theirs is a relationship that stretches nearly a half-century. When Jimmy Carter launched his audacious bid for president in 1976, Joe Biden was a little-known first-term senator who gambled on endorsing the peanut farmer-turned-Georgia governor.

Carter never forgot Biden’s early affirmation on his way to an upset victory. Biden was the first U.S. senator to back Carter’s underdog campaign, and over the years a relationship shaped by politics turned into something else: a warm and lasting friendship.

Now Carter is nearing his 100th birthday in hospice care in his hometown of Plains, too weak to travel to the Democratic National Convention in Chicago. And Biden is entering the twilight of his political career, reluctantly ceding his reelection bid to his No. 2.

If the first day of the convention marked a handing of the baton from Biden to Vice President Kamala Harris, the second commemorated another generational transition.

Paul Sancya/AP

Paul Sancya/AP

Jason Carter, the heir to his famous grandfather’s political legacy, delivered a speech honoring the former president’s long record in public service. It also formed a symbolic link between Jimmy Carter’s party and Harris, the newly minted Democratic standard-bearer.

“Just like the torch has been passed from Joe Biden to Kamala Harris, the torch has been passed from Jimmy Carter to Jason,” said former Gov. Roy Barnes, the last Georgia Democrat to serve as governor. “It’s a transition with a legacy.”

During the younger Carter’s remarks, he drew loud applause when he made clear his grandfather “cannot wait to vote” for Harris. And he made a series of comparisons between the Nobel laureate from South Georgia and the first woman, Black person and person of South Asian descent to serve as vice president.

“His legacy is measured by the lives he has touched and the good he has done. Kamala Harris carries my grandfather’s legacy,” Carter said. “She knows what is right, and she fights for it.”

For a 99-year-old widower who has been convalescing in southwest Georgia much of the decade, Jimmy Carter remains a surprisingly frequent target of another Oval Office veteran.

Donald Trump routinely savages him on the campaign trail, saying the Georgian must be “happy because he had a brilliant presidency compared to Biden.” Carter’s family prefers to draw a contrast between the two rather than engaging in recriminations, with Jason Carter emphasizing his grandfather’s devotion to “honesty and integrity.”

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Arvin Temkar/AJC

But the former president has maintained a close friendship with Biden, who recalls fondly his March 1976 journey to Wisconsin to endorse Carter. He was one of the few politicians outside of Georgia who would be seen publicly with the Georgia governor, let alone endorse him.

“Some of my colleagues in the Senate thought it was youthful exuberance on my part,” Biden said in a video tribute in the 2021 documentary “Carterland.” “Well I was exuberant.”

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He added: “As I said then: ‘Jimmy’s not just a bright smile. He can win, and he can appeal to more segments of the population than any other person.’”

Watching from afar, Barnes often marveled at their bond.

“A lot of political alliances are made as agreements of convenience. Theirs is a multidecade friendship. They really like each other,” Barnes said. “And that is rare in politics, just let me tell you. Who’s your friend today may be your enemy tomorrow. That’s not the way it is between those two.”

A last wish

Carter would return the praise throughout their careers, including calling Biden his “first and most effective” ally in the U.S. Senate at the Democratic convention in 2020. After Biden defeated Trump in that election, the president and his wife, Jill, visited Carter and his wife, Rosalynn, in their tiny southwest Georgia hometown, memorializing the pilgrimage with a photo that quickly went viral.

courtesy of The Carter Center

The ritual on Tuesday brings fresh attention to the younger Carter, a former state senator who was the Democratic nominee for Georgia governor in 2014.

As chair of the Carter Center, Jason Carter remains knee-deep in complex human rights issues and is routinely mentioned as a candidate in 2026, when an open governor’s race is on the ballot.

The issues that shaped his decade-old defeat to Republican incumbent Nathan Deal wouldn’t be easily recognizable in today’s environment. Abortion rights, gun control and culture war issues took a back seat to fights over the state’s byzantine school funding formula.

Georgia Democrats then regularly ran away from national party leaders; now they mostly run toward them. And back in 2014, Georgia was an afterthought on the presidential trail. Now it’s a battleground, solidified by Biden’s upset 2020 victory.

With the state in the crosshairs again, the former president recently surprised his relatives. Lately, they say, Carter has seemed more interested in national politics and attuned to the November race. When his son Chip gently asked him about his upcoming century-mark milestone, the former president had something else on his mind.

“I’m only trying to make it to vote for Kamala Harris,” he said.

Carter recently made a final request to his loyal friend. Biden let slip to a group of donors that the former president asked him for a final honor during that 2021 visit: to deliver his eulogy.