Joe Biden: I'll 'Work Like Hell' for Bernie Sanders If He Wins Nomination, Buttigieg Can't Win Black Vote

Former Vice President Joe Biden said he would "work like hell" for Vermont Senator Bernie Sanders if the latter receives the Democratic nomination, but Biden noted that it's his own campaign that will bring out black voters and propel him to victory.

Speaking with ABC News' George Stephanopoulos in an interview which aired Sunday, Biden reiterated his belief that he's the only Democratic presidential candidate who has the broad appeal necessary to win over moderate and minority voters. Biden said Sanders' label as a "Democratic Socialist" is too much of an "uphill climb" for the senator to defeat President Donald Trump in the general election.

Biden also said that former South Bend, Indiana Mayor Pete Buttigieg's inability to draw African-American voters shows he doesn't have what it takes to win "across the board." Update: Buttigieg campaign response below.

The former vice president brushed off his fourth-place Iowa caucus finish, describing himself as the "underdog" going into the New Hampshire primary Tuesday and beyond.

Stephanopoulos asked Biden if he believes Democrats will be able to defeat Trump if they "have to defend socialism" against Republican attacks. Biden repeatedly noted Sanders has labeled himself a "Democratic Socialist" and he is not "putting that label on Bernie."

"I think it's going to be incredibly more difficult. Look, if I don't get the nomination and Bernie gets it, I'm going to work like hell for him. But I tell you what, it's a bigger uphill climb running as a senator or congressperson or as a governor on a ticket that calls itself a Democratic Socialist ticket ... Bernie's labeled himself, not me, a 'Democratic Socialist.' I think that's the label the president's going to lay on everyone running with Bernie if he's the nominee. This is going to be a field day for the president."

In late January, Biden declined to tell reporters he would support Sanders if the Vermont senator won the nomination despite having previously vowed to back any Democrat "regardless" of who is nominated. "I'm not going to make judgments now," Biden said in Muscatine, Iowa, six days before the caucuses. "I just think that it depends upon how we treat one another between now and the time we have a nominee."

But Biden maintained that there is a united Democratic front against Trump despite the ongoing primary race.

"The thing that changes this election is that everybody in the Democratic Party is united on one thing: we have to beat Donald Trump. And in order to do that, everybody knows you've got to bring out the black vote and the brown vote. And you've got to be able to do it. I've been able to do that so far," Biden continued.

Biden's campaign released an ad over the weekend ridiculing Buttigieg's mayoral record in South Bend, Indiana, where he demoted a black police chief and reportedly pushed out the city's African-American fire chief, although Buttigieg's campaign maintains he simply retired. Biden told Stephanopulous that Buttigieg simply "hasn't been able to unify the black community" around his campaign.

Entrance polls reported by ABC News showed Buttigieg came in second, ahead of Biden, among among non-white Iowa caucusgoers. The Buttigieg campaign issued a statement responding to Biden's critical digital advertisement:

"At this moment, the American people are crying out for something completely different from this classic Washington style of politics. While Washington politics trivializes what goes on in communities like South Bend, South Bend residents who now have better jobs, rising income, and new life in their city don't think their lives are a Washington politician's punchline. Pete's on the ground experience as mayor, turning around a Midwestern industrial city, is exactly why he is running for president."

Biden continued Sunday, "In order to win, George, you're going to have to be able to win states like Pennsylvania," Biden said. "You're going to have to be able to win Florida. To have to be able to win a lot of places that, in fact, have very diverse populations. And so the assertion that he's ready across the board, I don't see it. I haven't seen it yet."

"Look, the black community knows me and I know them. And I think we take it for granted much too much," Biden said, adding "my biggest concern about the African-American community with the Democrats is: most of it was taken for granted. They just take it for granted that they're going to show up."

Stephanopoulos reminded Biden that his fourth-place finish in Iowa behind Sanders, Buttigieg and Massachusetts Senator Elizabeth Warren is historically a solid indication that he is unable to win the Democratic nomination.

"This is a long, a long race. I took a hit in Iowa and I'll probably take a hit here," Biden said. "In New Hampshire I'm an underdog because of the fact that you know, Bernie won this place by 20 points last time. The neighboring senators have gigantic influence. And so I think I'm an underdog."

Symone Sanders, who was Bernie Sanders' national press secretary during his 2016 presidential campaign, touted the campaign of her new boss, Joe Biden, while speaking with reporters after Friday's debate.

"We know it's going to be a fight. We know it might be an uphill battle. But the reality is, we are still in this race," she said. "The reality is that we have said from the beginning that you should view these first four nominating contests as a package, which means Iowa, New Hampshire, Nevada, and yes, South Carolina."

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Former Vice President Joe Biden said he would "work like hell" for Vermont Senator Bernie Sanders if his opponent receives the Democratic nomination, but Biden noted that it's his own campaign which will bring out black voters and propel him to victory. Screenshot: ABC This Week | Twitter
Joe Biden: I'll 'Work Like Hell' for Bernie Sanders If He Wins Nomination, Buttigieg Can't Win Black Vote | Politics