SOUTH BEND, Ind. — Pete Buttigieg is rarely home these days as he scoots from South Carolina to New Hampshire to Iowa in pursuit of primary voters.
But back in South Bend, a fierce fight is underway between his campaign and some of his top rivals over Mr. Buttigieg’s impact on black residents.
With Mr. Buttigieg, the city’s two-term mayor, struggling to win African-American support, his campaign has turned to highlighting black leaders in South Bend who vouch for him, as a means of countering a run of negative news stories.
“One of the things we’ve seen is that the black voters who know me best, in South Bend, that’s where we have a lot of our best support,” Mr. Buttigieg said Friday in Iowa, as his campaign began posting “South Bend Stories” — short videos of black and Latino supporters in his hometown — on its website.
At the same time, Buttigieg’s rivals are targeting his record with South Bend’s minority population, which accounts for 40 percent of the city’s population. Events took a tense turn last week at a gathering of black South Bend leaders who were voicing support for Mr. Buttigieg. As a City Council member, Sharon McBride, was praising the mayor’s “tremendous” impact in her district, a man grabbed the microphone and shouted, “Who chose these black leaders?”
South Bend residents identified the protester on social media as a supporter of Senator Bernie Sanders of Vermont. The Sanders campaign disavowed the tactic and the individual.
On Sunday, in an interview that aired on “Axios on HBO,” former Vice President Joseph R. Biden Jr. lobbed a critique at the mayor, saying “Mayor Pete obviously has had difficulty garnering black support in his home city.”
Mr. Buttigieg’s rivals to his left, Mr. Sanders and Senator Elizabeth Warren of Massachusetts, have openly taken aim as he has surged in Iowa and New Hampshire. Mr. Biden has sought to scuff up the mayor as a potential threat to Mr. Biden’s support from moderates. The Biden campaign recently trumpeted the endorsement of Oliver Davis, a black South Bend council member in a close-to-home rebuke of Mr. Buttigieg.
On Saturday, the pro-Sanders group Our Revolution rolled into town for the first in a series of national rallies, a choice of locale that was hardly a coincidence. The rally, not as chaotic as the earlier event on Wednesday, was at the West Side Democratic Club, a venerable dive bar and political hall, where posters for kielbasa and beer still hung from a Polish festival.
Kat Redding, a Sanders supporter, invoked a fatal shooting this year of a black resident of South Bend by a white police officer. “When it comes to holding police accountable, Mayor Pete is not a man of action,” she told the crowd.
Perceptions of Mr. Buttigieg among black voters nationally — he polls in the low single digits among them — have been shaped by wide news coverage of the police shooting in June. It exposed a history of distrust of police by some black residents. That is not a phenomenon unique to South Bend — a city with a famous university, Notre Dame, but also many poor and working-class residents. African-Americans make up 26 percent of the population, and the local black poverty rate is almost twice the national rate. In a presidential debate, Mr. Buttigieg acknowledged he had failed to increase diversity on the police force.
But Mr. Buttigieg’s record over eight years also includes many initiatives that backers of the mayor here say benefited minority residents.
“The narrative for so long now for South Bend has been that there’s no blacks in support of the mayor,” said Ms. McBride, who traveled as a surrogate for Mr. Buttigieg in South Carolina and helped organize the South Bend gathering last week for local black leaders who support the mayor. Although the Buttigieg campaign promoted the event, the speakers said it was their idea.
Among them were two council members and three pastors, including Michael Patton, the president of the local N.A.A.C.P. chapter. “Pete is someone who has done significant work in our community,” Mr. Patton said.
He and the others ticked off initiatives under Mr. Buttigieg: a small-business resource center on the West Side where minority residents are concentrated; the hiring of the city’s first diversity officer; legal help for tenants facing evictions; and funding for home repairs in historically marginalized neighborhoods.
“Mayor Pete has spent more taxpayers’ dollars on the West Side of South Bend than the previous 30 years,” Dave Thomas, a commissioner of St. Joseph County, told the gathering.
Elected in 2011, Mr. Buttigieg ran on a promise to turn around his Rust Belt city. In his most visible success, he funded downtown infrastructure and gave incentives to real estate developers to revive the urban core. Critics say the investments were not spread equally to poor neighborhoods, and prosperity has passed them by. In South Carolina recently, Mr. Buttigieg claimed to have cut the black poverty rate “by more than half,” a statement that did not withstand a fact checker’s scrutiny.
There is scant polling of Mr. Buttigieg’s level of support from minority voters in South Bend. But election results tell part of the story. Seeking a second term in 2015, the mayor easily held off a primary challenge from an African-American council member. The mayor carried his challenger’s own district, though he lost several of its precincts with dense concentrations of black residents.
Two prominent black critics of the mayor on the current council — Mr. Davis, the Biden supporter, and Regina Williams-Preston, who was a 2016 national convention delegate for Mr. Sanders — both ran for mayor this year to succeed Mr. Buttigieg. They finished poorly in the primary, failing even to carry their own West Side neighborhoods.
Mr. Davis said Mr. Buttigieg’s “Douglass Plan” — released over the summer to address racial disparity in the United States — is unconvincing because the mayor did not follow its prescriptions at home, such as directing city contracts to minority-owned businesses.
Ms. McBride said Mr. Buttigieg did implement aspects of the Douglass Plan in South Bend, including raising the minimum wage for full-time city employees to nearly $15 an hour. She cited inspections of rental properties to protect tenants from lead paint and a program to build affordable houses on the Southeast Side, another area with a large minority community.
Ms. McBride argued that the mayor rightfully prioritized downtown development to give people reason to invest and live in South Bend, which was named a “dying city” by Newsweek the year Mr. Buttigieg was first elected but has since grown in population after decades of decline.
“You have to start at the heart” of the city, she told the gathering of black leaders and Buttigieg supporters. In recent years, she said, the mayor has focused economic development on the city’s neighborhoods.
She was abruptly cut off by the protester, who wore a Black Lives Matter T-shirt, and shouted, “Where are the black leaders that don’t have three-piece suits, leather jackets and nice jewelry!”
He snatched the microphone and denounced the meeting as a farce. Audience members scuffled to remove him, including a woman who raised her cane. He was eventually escorted to the back of the room, where other Black Lives Matter and Sanders supporters continued to heckle the speakers.
“I happen to be a black leader with a leather jacket on,” Ms. McBride said when she regained the microphone. “I don’t get intimidated.” She said the city under Mr. Buttigieg had compiled a record of “empowerment” projects.
“You may not like it, but you will respect it,” she said.