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(CNN) —  

Bernie Sanders’ biggest selling point in 2016 was that he was the only person in the Democratic primary running not named Hillary Clinton.

2020 won’t be that way. And to be successful, he’ll have to earn every vote he can get.

This field will be massive, and in many ways, everyone is running as not Hillary Clinton (note Amy Klobuchar and Beto O’Rourke’s digs at Clinton in their Wisconsin appearances).

And while he certainly pushed the party left on a number of issues, including health care and college tuition, it’s the Democratic Party that has pushed Sanders to the left on race and identity.

So, where does that leave Sanders, particularly with African-American voters, the key group that he struggled with against Clinton? In South Carolina, he lost by nearly 50 points (50!) – and Clinton won 87% of the black vote.

That smackdown ended up being a preview of how Sanders would do throughout the delegate-rich South, highlighting weaknesses in the top echelons of his campaign team, which was largely white and male. Aides from 2016 say that they had a plan to reach black voters, but were largely ignored. Some also complain that they were often treated as tokens or props, particularly after Sanders was shouted down by a group of Black Lives Matter protesters at an event in Seattle.

He did have some appeal and successes, however.

“To see him among black people is a sight to behold. When I traveled with him, they gravitated to him the same way that white people did, particularly young black people,” said Nina Turner, a top surrogate for Sanders in 2016 and a CNN commentator. “He really has a certain appeal to people who are 35 and younger. He had that broad base appeal. In places like Texas and Ohio or Michigan, when he went to Flint, black people gravitated toward him. And they believed him in his message.”

Sanders bested Clinton among black voters under age 30 in an array of states, yet that group of voters didn’t show up in primary contests in the same way that voters over age 60 did.

Sanders is a Democratic socialist who has been hesitant to talk about race and showed a disdain for identity politics on one hand while never acknowledging it on the other hand.

But, there are clear signs that he has evolved on these issues.

“I wouldn’t say so much he has evolved as many more lessons learned,” Turner said. “He listens, he is a student of the game. He sees a lot as class-based, it’s his predominate lens but it’s not his only lens.”

Naming it

01:24 - Source: CNN
Sanders: We have a president who is a racist

In 2016, Sanders was hesitant to call Trump a racist during a debate with Clinton. But during a recent trip to South Carolina to honor the legacy of Dr. Martin Luther King, Jr, he called him a racist.

“Has he learned lessons since 2016, yes,” said Symone Sanders, the national press secretary for Sanders’$2 2016 bid. “He has been actively working since 2016 to reach out to various communities to be on the ground and listen to folks. He has been to South Carolina a few times, which is really important. But some of the language is going to be problematic.”

Indeed, his comments about diversity and racism in a recent GQ magazine article drew the ire of black progressives.

He suggested that some of his opponents “think that all that we need is people who are candidates who are black or white, who are black or Latino or woman or gay, regardless of what they stand for, that the end result is diversity.”

Symone Sanders disagreed.

“Nobody is saying that, and in a race where there are Latinos and women and black women, people will use it against him,” Sanders said. “I don’t care how many times you go to South Carolina. You say things like you said to GQ because you think it’s appealing, it’s alienating to some folks. As a young black millennial, I don’t like hearing it because it speaks to a fundamental misunderstanding about race and gender and what people are looking for.”

Asked why he thought Stacey Abrams and Andrew Gillum lost their gubernatorial bids, the Vermont senator said, their losses weren’t because they were too progressive.

“(A) lot of white folks out there who are not necessarily racist … felt uncomfortable for the first time in their lives about whether or not they wanted to vote for an African-American,” Sanders told GQ.

02:55 - Source: CNN
Can Bernie Sanders win over black voters?

Turner called him up after she saw the comments.

“Senator, by definition if somebody declares they aren’t voting for somebody because they are black, they are racist,” Turner said she told him. “And he acknowledged it. And he got it automatically, he said, ‘Yes, you are right.’ “

Winning black votes will remain a challenge for Sanders, even with his focus on race and class, and his high name ID.

But Killer Mike, who stumped for Sanders in 2016, is still with him and could continue to be a powerful surrogate. On a recent appearance on ABC’s “The View,” he wrapped Sanders in the legacy of King.

“What Bernie’s campaign reminded me is that my fight is there, with the working class, with the poor, with the proletariat. It’s not with the political oligarchy, it’s not with those who are rich and affluent enough to escape politics, it’s firmly with the working class,” he said. “That’s why I support him now, that’s why I support him then. I think he is is the only person that can be Trump, I do.”