Democratic presidential candidate Pete Buttigieg is facing a more intense spotlight on his past leadership on issues of race and policing as he tries to translate his strong showing in Iowa and New Hampshire into support in more diverse states.

Buttigieg, who spent eight years as mayor of South Bend, Indiana, has tripped up in recent days as he was grilled about his record, including the racial disparity in marijuana arrests in South Bend and decisions that led to him having no African American leaders in his administration during a crucial stretch of his tenure in a city where more than a quarter of residents are black.

The 38-year-old is trying to address those questions with a flurry of advertisements featuring black supporters and an appeal to minority voters who, like many in their party, are focused on which candidate is best positioned to beat President Donald Trump in November.

“Before anybody cares what’s in your plans, they want to know if you’re a serious contender, and I think up until we had the results we did here in Iowa and New Hampshire, it was difficult for us to prove,” Buttigieg said Wednesday on PBS. “Now the process of proving it is underway.”

Buttigieg, who was virtually unknown in national politics a year ago, essentially tied Vermont Sen. Bernie Sanders in Iowa and placed a close second in New Hampshire. But his strong showings in those opening contests hasn’t scared off other more moderate candidates, in part because Buttigieg’s ability to court nonwhite voters is unknown.

Tracy Arnold, a 61-year-old former police office from Chattanooga, Tennessee, which votes on March 3, said Buttigieg “didn’t seem to be as active when it came to black people’s concerns,” when he was mayor of South Bend. And he said he questions whether Buttigieg is sincere when he talks about criminal justice and inequality issues now.

“It makes you curious and somewhat suspicious,” said Arnold, who is black. “You had an opportunity to do that when you were mayor, and your report card wasn’t all that great.”

Buttigieg’s campaign is scrambling to address those concerns, particularly in South Carolina, where black voters make up about 60 percent of the Democratic electorate.

His campaign says it has 55 staffers in the state and has been running digital, TV and radio ads featuring black supporters from South Carolina and South Bend. South Carolina state Rep. J.A. Moore, who is black, endorsed Buttigieg this week, calling him “the only viable candidate to build a cross-racial, rural, urban and suburban coalition to win in November.”

But as the Feb. 29 South Carolina primary nears, the former mayor continues to face questions about his record. He was pushed several times during Friday’s debate to explain the racial disparity in marijuana arrests in his city. An analysis by The Intercept found that between 2012 and 2018, a black resident of South Bend was more than four times as likely to be arrested for possessing marijuana than a white resident, compared with 3.5 times more likely in Indiana, or three times as likely nationally.

Buttigieg first dodged, then changed the subject. ABC News moderator Linsey Davis pushed him to answer.

“How do you explain the increase in black arrests in South Bend under your leadership for marijuana possession?” she pressed.

Buttigieg then cited a different statistic, overall drug arrests, that spun his record in a more favorable light, prompting a rebuke from Davis to answer the question she had asked.

He ultimately blamed the disparity on a strategy his city had adopted to target gun violence and gang violence.

The next morning, former Vice President Joe Biden released a withering attack ad that highlighted decisions Buttigieg made to push out the black police chief and fire chief.

An investigation by The Associated Press, published last month, found that South Bend Fire Chief Howard Buchanon retired from the department shortly after Buttigieg took office in 2012 because the new mayor chose a different chief. That appointee was a white man, and Buchanon is black.

Two months later, Buttigieg demoted Police Chief Darryl Boykins, the city’s first black police chief.

Buttigieg has said that he removed Boykins and fired a second employee, a white woman, because of a “thinly veiled” message from federal prosecutors that they might otherwise face criminal charges for recording phone calls at the police station. But that explanation has been called into question by several people involved in the case.

Their removals left no black leaders in Buttigieg’s administration, and he did not hire any African American staffers in a top position until more than a year after the police chief’s demotion — a decision that rankled many black residents.

An analysis by the AP found that more than three-quarters of the people Buttigieg hired were white, even though South Bend’s population is 53% non-Hispanic white, and more than one-quarter black.

Buttigieg says black voters and leaders in South Bend know him best and are backing him. His campaign has highlighted several black officials from South Bend and other community leaders who have endorsed him, including the head of the local chapter of the NAACP.

However, several other black leaders in South Bend have been critical of Buttigieg’s leadership, including current and former members of the City Council, several black pastors and others.

Pastor Wendy Fultz, a leader in the activist group Faith in Indiana, worked with Buttigieg and his administration after the fatal police shooting of a black man, Eric Logan, last summer. She was critical of how Buttigieg handled the situation, telling the AP on Thursday that while he did some good things, she did not believe he made it a priority to address problems with the police department.

“He will not get my vote, simply because I don’t feel like his heart is with everybody,” said Fultz, who has not endorsed any other candidate.