More than any president in recent memory, and maybe ever, Jimmy Carter’s legacy was defined by the good works he did after leaving the White House.

As president, though, he struggled with rising inflation, diplomatic setbacks and a growing sense that he was simply overmatched in the role — a feeling that led to a bitter but ultimately unsuccessful 1980 primary challenge from then–Massachusetts Sen. Ted Kennedy.

“In 1980, Jimmy Carter was viewed as weak by folks in Washington, D.C., by many in the Democratic Party,” Peter Ubertaccio, a political scientist and vice president of academic affairs at Stonehill College, said on GBH’s Talking Politics.

Ubertaccio said Carter was a moderate who represented those within the Democratic Party who had long been battling with liberals. Kennedy used that infighting as an opportunity to challenge the sitting president’s reelection bid. That theme even popped up in Kennedy’s memorable speech at the Democratic National Convention, effectively calling out Carter — the chosen nominee — for abandoning the soul of the party.

"It is the glory and the greatness or our tradition to speak for those who have no voice, to remember those who are forgotten, to respond to the frustrations and fulfill the aspirations of all Americans seeking a better life in a better land. ... We cannot let the great purposes of the Democratic Party become the bygone passages of history."
Sen. Edward Kennedy, 1980 Democratic National Convention

Paul Watanabe, a political scientist and director of the Institute for Asian American Studies at UMass Boston, cautioned against underestimating Carter’s liberal bona fides. He noted that, among other things, Carter created the departments of Education and Energy and fought segregation in his home state of Georgia.

Watanabe described Kennedy’s challenge as largely driven by personal ambition, and called it “the most significant challenge” from a politician in an incumbent president’s own party.

The contest also had lasting implications for Democrats moving forward, notably, the types of candidates we’ve seen from the party and who have won the White House.

“There was a sense in which we saw Jimmy Carter as an accidental, surprise choice in 1976. We saw a similar dynamic in terms of Bill Clinton in 1992. He was a bit of a surprise. And Barack Obama subsequently as well,” Watanabe said.

“These are individuals who came from the outside ... they were not individuals like Ronald Reagan, who was well-known, or George Bush, who was vice president, or even somebody like George Bush Jr., who was part of the political legacy. Or even Donald Trump, who’s a well-known figure,” Watanabe said. “The introduction of new faces into the presidency —something that Jimmy Carter really helped to start — has been the success of Democrats since that time.”