Oliver Davis, the longest-serving African American man on the Common Council of South Bend, Ind., endorsed Joe Biden over Pete Buttigieg, the city's mayor, reports Politico.

Why it matters: The endorsement highlights two common criticisms of Buttigieg: his lack of political experience beyond local government and his struggle to appeal to black voters.

Buttigieg is polling at 0% among black South Carolina Democrats in a Quinnipiac poll released Monday. That's a key demographic in a key early state on the primary calendar.

What he's saying: "I believe that Vice President Biden has demonstrated throughout the years by having a steady hand, he can help lead us through these times, and with all of the challenges we face nationally and now even internationally, he has the relationships, has the skills, and I think he can bring us together in different ways," Davis told Politico.

The big picture: Several 2020 Democratic candidates attacked the South Bend mayor on the debate stage this week for not having enough experience to sway black voters.

Tulsi Gabbard criticized Buttigieg for his lack of experience on foreign policy.

After Kamala Harris asked him to address how he plans to appeal to black voters, he said he welcomes "the challenge of connecting with black voters in America who don't yet know me."

What to watch: Buttigieg has has ascended to the top the polls in Iowa — which is over 90% white — but it remains to be seen if he can translate potential early success there across the country.

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