“100% a SELLOUT!” says one Bernie Sanders supporter on Twitter. “EPIC FAIL!!!!!”

After his endorsement of Hillary Clinton, some Sanders faithfuls are decrying his reversal as an act of betrayal, calling him a “spineless piece of trash loser traitor” and worse.

But whether you think Bernie’s a loser or a sellout depends on what you think his political purpose and utility have been all along. Of course, his supporters wanted him to win the nomination, and eventually the presidency, but also-rans have proven highly influential in the past.

Take George Wallace, the staunchly racist, segregationist Alabama governor who ran for president four times. Three of those times he ran as a Democrat, and while he was never nominated, he shifted the conversation outside the party’s comfort zone and dictated the terms of the political discourse. Ideologically, he was the opposite of everything Bernie stands for, but like Bernie he threw his weight around in the Democratic party to great political effect.

George Wallace, 1964. (Library of Congress)

“He was the most influential loser in twentieth-century American politics,” writes Dan Carter in his biography of Wallace. Though he’s mostly remembered as a villain — a “prophet without honor,” Carter writes — Wallace was a prophet all the same, the pied piper of Southern segregationists. In the early 1960s, Southern whites still tended to vote Democrat, alongside working-class union members and middle-class liberals. Wallace energized the white Southern faction of the Democratic party, and they started to see themselves as a distinct political contingency — a movement.

“White Backlash Evident In Voting,” declared a New York Times headline in 1966. “The backlash first became a potent factor in the 1964 Presidential campaign when Gov. George C. Wallace of Alabama sought to arouse national opposition to the civil rights bill of 1964.” Following Wallace’s lead, and emboldened by his outspoken racism, “Whites expressed fear that Negroes were moving too fast on civil rights, were trying to move into their neighborhoods, and were committed to violence in their struggle to win their rights.”

For years in the 60s, Democrats attempted to retain the support of this important voter base. John F. Kennedy and Lyndon B. Johnson had steered the party in the direction of integration and civil rights, but fearful of losing the Southern white vote, some Democrats doubled down on segregation. “In many races, Democrats are even stronger foes of integration drive,” declared the New York Times in another 1966 article.

“By 1968, with the anti-war movement, counter-culture, and surge in violent crime beginning to alarm large swaths of middle America,” writes Damon Linker at The Week, “Wallace touched a broader and deeper nerve, expressing a widespread culturally populist revulsion among a certain segment of white Americans.”

Bernie’s grassroots campaign has also clearly touched a nerve — albeit a less odious one — and has been significant in scale and influence. His run has shifted Clinton and the Democratic party decidedly to the left. Hillary Clinton began making concessions to this contingent earlier this year, and if she wants to retain Bernie’s legion of supporters, she can’t let up just because his endorsement is now official.

History shows that a candidate doesn’t have to win the nomination to change the political landscape. Bernie’s movement has its own agenda, distinct from the party’s — and the party is listening.