South Bend, Ind., Mayor Pete Buttigieg is polling at 0% among black voters in the key early primary state of South Carolina.

After coming out of nowhere to emerge as a contender for the 2020 Democratic nomination, Buttigieg has hit a bit of a wall, and one big reason is his failure to appeal to black voters, who make up a substantial portion of the Democratic electorate.

This was highlighted in a poll released Sunday by the Post and Courier, which, like many other polls, showed former Vice President Joe Biden well ahead, with 46%, to 15% for Sen. Bernie Sanders, I-Vt., the nearest competitor. But given the importance of black voters in the state, I was fascinated by this breakdown by race posted by Steve Kornacki, who notes that black voters made up 61% of the Democratic primary electorate in 2016:

Post & Courier SC Dem poll by race:



White

Biden 38%

Buttigieg 18%

Sanders 16%

Warren 11%

Harris 9%

Booker 2%

Klobuchar 2%

O’Rourke 2%

Bennet 1%

Delaney 1%

Gabbard 1%

Yang 1%



Black

Biden 58%

Sanders 15%

Harris 12%

Warren 5%

Booker 5%

Yang 3%

Abrams 2%

O’Rourke 1%

Buttigieg 0% — Steve Kornacki (@SteveKornacki) May 13, 2019

What first jumps out is Biden's strength among black voters — he actually does 20 points better among black voters than among whites. Any rival hoping to take him down is going to have to do a much better job connecting with the community.

But what's also extraordinary is the significant race gap in Buttigieg's support. He's in second place among white voters, with 18% of the vote. And yet, he's at zilch among black voters. This is consistent with other polls nationally and at the state level.

Well aware of the problem he has with black voters, Buttigieg has tried to address it by lunching with Al Sharpton, explaining some decisions he made as mayor that were criticized by the black community, speaking about the need to have more voices join his campaign, and publicly checking his white privilege.

His efforts to reach this skeptical but crucial group of voters have obviously yet to make any headway thus far, however, and if he doesn't find a way to change that, his candidacy will go nowhere.

[Read more: South Bend's Buttigieg trails in Indiana, 3rd behind Biden, Sanders]