As Pete Buttigieg struggles for momentum going into the South Carolina Democratic primary and Super Tuesday, two members of Congress from the Washington region are traveling the country to promote his presidential campaign.

Reps. Don Beyer (D-Va.) and Anthony G. Brown (D-Md.) were early endorsers of the ­38-year-old former mayor of South Bend, Ind., who they say has the personal story and calm demeanor to unite a nation divided by President Trump.

Brown, who served in the Army for more than 30 years and is vice chairman of the House Armed Services Committee, was drawn to Buttigieg because of his military service and foreign policy chops.

Beyer said he was impressed by Buttigieg’s intelligence and résumé — he speaks multiple languages, plays classical piano and was a Rhodes Scholar. Buttigieg’s even temperament, Beyer said, reminds him of former president Barack Obama’s ability to stay calm under pressure.

Seven members of Congress have endorsed Buttigieg, compared with nine for Sen. Bernie Sanders (I-Vt.), 13 for Sen. Elizabeth Warren (D-Mass.), and 50 for former vice president Joe Biden.

Most members of Congress from Virginia and Maryland have not endorsed a candidate in the contest. In addition to Beyer and Brown, a few exceptions are Rep. Jamie B. Raskin (D-Md.), who backs Warren, and Reps. A. Donald McEachin (D-Va.) and Elaine Luria (D-Va.), who are Biden supporters. Rep. David Trone (D-Md.) endorsed John Delaney, his predecessor in Congress, before Delaney dropped out of the race.

Buttigieg won the most delegates in the Iowa caucuses on Feb. 3 and did well in the New Hampshire primary a week later. But he trails in South Carolina, which will vote Saturday, and is in the middle of the pack in Virginia, one of 14 states that will vote on Super Tuesday on March 3.

Former South Bend, Ind., mayor Pete Buttigieg, who is looking to resonate with voters ahead of Super Tuesday, held a town hall in Arlington, Va., on Feb. 23. (The Washington Post)

He has struggled to attract black voters, a key demographic in South Carolina. Brown, 58, the only member of the Congressional Black Caucus (CBC) to endorse Buttigieg, has been touring the country, including the Palmetto State. He tells voters they will like the former mayor once they get to know him.

He and Buttigieg first spoke at the annual CBC gala in September. The pair, both Harvard University graduates, bonded over their shared military service.

“There’s that special connection that people who have served have,” said Brown, who was elected to Congress in 2016, representing a district anchored in Prince George’s County.

“Much like when two fraternity brothers or sorority sisters meet . . . . I’m Army, he’s Navy; I don’t hold that against him.”

They met again at a D.C. coffee shop in November — Buttigieg drinks coffee all day, Brown had decaf, the congressman said — and arranged for Brown to spend the weekend after Christmas in Iowa. They drove together from place to place, and Brown was hooked.

It didn’t hurt that two of Buttigieg’s top campaign staff members worked for former Maryland governor Martin O’Malley, under whom Brown served as lieutenant governor for eight years.

Brown formally endorsed Buttigieg in January, and he has traveled nearly every weekend since then: Iowa, then New Hampshire and Michigan.

Last weekend, he flew from Nevada to Colorado to South Carolina, where he stepped off a red-eye flight at 5 a.m. and he was in an African American church by 10 a.m., a full slate of barbershop visits, dinners, interviews and rallies on his agenda.

“We want to make sure we’re engaging African American voters where they are,” Brown said. “We know that visiting churches, which I’ve been doing all my life, is important.”

He worked the spin room in Charleston, S.C., after Tuesday night’s debate and was back in Washington on Wednesday morning.

Among his central messages: Sanders is too divisive to win the general election or help down-ballot Democrats retain vulnerable House and Senate seats.

Buttigieg is “best to defeat Donald Trump,” Brown said, “but particularly to voters in South Carolina, if you want [Democrat] Jaime Harrison to defeat [Republican Sen.] Lindsey Graham, Pete is your best. . . . He’s not polarizing like other candidates.”

Beyer, also a former lieutenant governor, learned about Buttigieg from his youngest child, who encouraged his dad to watch a video of the then-mayor speaking at a Politics and Prose bookstore in Washington.

In April, Beyer became the first member of Congress to endorse Buttigieg.

“He hasn’t disappointed in the 10 months since I signed on,” said Beyer, a three-term congressman who is 31 years Buttigieg’s senior. “He just gets better.”

Like Brown, Beyer spends a lot of time talking about Buttigieg’s Douglass Plan, named after abolitionist Frederick Douglass. Amid some missteps and criticism that Buttigieg was late to address problems between his city’s police department and black residents, his plan aims to change the nation’s criminal justice, education and health-care systems to help empower African Americans.

In December, Beyer took it upon himself to write to the more than 50 members of the CBC touting the plan.

“I am impressed with its comprehensiveness and specific proposals to address the ­400-year legacy of slavery, discrimination, Jim Crow, brutality, and more suffered by black Americans,” his letter said. “But I also realize that you have spent your lifetime working to overcome these injustices.”

Buttigieg — and Beyer — faced a friendly crowd Sunday in Arlington, where the mayor spoke at a town hall gathering at Washington-Liberty High School.

Beyer, a former car dealership owner and prolific Democratic donor, hosted Buttigieg at his home in Alexandria that evening for what the congressman said was Beyer’s most well-attended fundraiser ever.

Buttigieg’s strong debate performances have helped spur interest in his candidacy in Northern Virginia, Beyer said. But with a crowded field of candidates, and huge spending on television advertising by billionaire businessman Mike Bloomberg, there is no clear favorite in the state.

“It will be interesting to see how the non-Bernie center left and progressive left shakes out,” Beyer said. “I hope Pete will do well.”

Emily Guskin contributed to this report.