AP Photo/Charlie Neibergall
Democratic presidential candidate South Bend Mayor Pete Buttigieg speaks at the Carroll County Democrats Fourth of July Barbecue in Carroll, Iowa.

CARROLL — Pete Buttigieg stunned the Democratic presidential field with a nearly $25 million second-quarter fundraising haul. Now he needs to figure out how to use that money to build a campaign that can go the distance against nearly two dozen rivals — many of them better known — and ensure that enthusiasm from donors is matched by support from voters.

That poses big challenges for the 37-year-old mayor of South Bend, Indiana, who lags several of his top opponents in the number of staff on the ground in early states. He also has significant work to do to earn support of African American voters, a crucial constituency in the Democratic presidential primary.

Buttigieg said much of his emphasis will be on retail politics — more days like Thursday, when he blitzed across Iowa for a parade and picnics and one-on-one interactions with voters. The campaign also says it plans in coming months to add 100 people to a staff that started with six employees and now has about 200, as well as enlist a larger number of volunteers.

“The whole point of all that fundraising was to make sure that we have the organization we need to win,” Buttigieg told reporters after a town hall meeting in a sweltering Sioux City, Iowa high school gymnasium. “Obviously we got great news on that front, now we’ve got to put it to work.”

Buttigieg has been a source of both fascination and skepticism in the opening months of the Democratic primary. He was virtually unknown when he launched his campaign, but garnered attention with high-profile media appearances and a call for generational change in politics.

His fundraising prowess suggests he will be more than Democrats’ flavor-of-the-month candidate — he topped former Vice President Joe Biden’s haul and more than doubled the money raised in the second quarter by Sen. Kamala Harris, whose home state of California is the center of the Democratic fundraising universe. He’s attracted high-dollar donors, including “West Wing” actor Bradley Whitford and “Glee” producer Ryan Murphy, and his grassroots events, with tickets as low as $25, have drawn as many as 1,500 people.

Yet Buttigieg still faces questions about his experience and whether his appeal extends beyond wealthier donors and white voters.

“Ultimately you can raise all the money in the world but you need to figure out your pathway to win that nomination,” said Doug Thornell, a Democratic strategist.

Buttigieg’s biggest investment has so far been in Iowa, the overwhelmingly white state that kicks off the Democratic primary with a caucus on Feb. 3. The campaign has about 40 staffers on the ground there, more than it has in any other state, though Buttigieg’s team acknowledges that the caucus structure — in which voters are asked to attend local meetings to support their candidate — requires more boots on the ground to organize.

Buttigieg spent the July 4 holiday barnstorming the state and plans three more visits there this month, according to his campaign.

At a parade in Storm Lake, Iowa, Buttigieg’s reception was mixed. Dana Evans, who runs the local Vietnam Veterans of America chapter, greeted Buttigieg — who served in the Navy Reserve in Afghanistan — with an offer to ride in his group’s truck if he got tired of walking the parade route. He said he was glad to see Buttigieg out meeting with the “little people” and hoped he’d return to the area to talk more about veterans’ issues and national security.

But as Buttigieg walked the route with a group of mostly young volunteers, he remained unfamiliar to some in the crowd. One woman took a sticker from a volunteer then used it to type his name into her phone to find out who he was.

Carroll County Democratic Party Chairman Peter Leo said that’s why it’s important for Buttigieg to use his money to spend as much time in the state as he can. Leo introduced Buttigieg to the crowd gathered at a local park, where the candidate also took a turn at the grill and joined in a yard game tossing beanbags, often referred to as “bags.”

“Iowans love their retail politics. They want to have a chance to ask a question directly, meet you in person, shake your hand and really get a chance to, you know, just size you up one-on-one,” Leo said. “You know what I know about this area? They reward people who show their face.”