Rep. Chris Van Hollen (D-Md.) is running for the Senate seat being vacated by Sen. Barbara A. Mikulski. (Amanda Voisard for The Washington Post)

Chris Van Hollen’s résumé reads like a carefully crafted road map to the U.S. Senate. Twelve years in the state legislature, 13 in Congress. Special assistant to the speaker of the House. Ranking Democrat on the Budget Committee.

Yet the arsenal of credentials he has built to justify that promotion is now being used against him.

He faces a tough primary opponent in Rep. Donna F. Edwards, who in an election year that favors outsiders has dismissed his vast record as at best irrelevant and at worst a reflection of the clubby power structure she wants to change by becoming Maryland’s first African American senator.

Her attacks have deeply frustrated Van Hollen. The congressman has spent the past year telling Democratic primary voters about bills he shepherded and negotiations he led in the State House in Annapolis and in a Republican-dominated Congress — battles, he says, that prove his qualifications for the Senate.

For decades, he reminds them, he has worked with both black and white elected officials to defend liberal policies, driven by a belief in the importance of using politics to achieve progressive goals.

Rep. Chris Van Hollen gives a thumbs up to a honking supporter after holding a press conference at Johns Hopkins University Hospital in Baltimore on April 13. (Linda Davidson/The Washington Post)

“I see public service as a way to fight for justice and equal rights,” he said. “Anybody who knows me, knows me as someone who has been working in the trenches for a very long time.”

The equanimity that makes Van Hollen a good negotiator has left him open to his rival’s criticism. While he never endorsed cuts to Medicare or Social Security in the debt talks, such changes were discussed during debt negotiations — and Van Hollen said he was open to talking about them.

Edwards has used that position to try to impugn Van Hollen’s progressive credentials. The congressman’s irritation at those jabs is palpable.

In forums and debates, he sometimes shakes his head incredulously or mouths “not true” as Edwards speaks. He was particularly bothered by her claim that he is a “Wall Street Democrat,” those who know him say, given his commitment to closing tax loopholes for the financial industry.

“Do I enjoy it when somebody distorts my record for political purposes? Obviously not,” Van Hollen said. “But I enjoy being able to set the record straight.”

If Edwards’s attacks get under Van Hollen’s skin, it is her biography that has proved most challenging. Edwards would be the first black senator from Maryland and the second-ever black woman in the U.S. Senate, a chance at history she has trumpeted throughout her campaign. Van Hollen, in contrast, would merely be another of the white men who dominate the Senate. His voice has a tendency toward squeakiness, and he is drawn to details rather than dramatic declarations.

“He’s not a bumper-sticker guy,” said Rep. Bill Pascrell Jr. (D-N.J.).

Politician with ambition

Although Maryland Senate President Thomas V. Mike Miller Jr. (D-Calvert) recently described him as “born to” the U.S. Senate, Van Hollen insists he has not always wanted to be in the upper chamber — or even in elected politics.

Old friends disagree.

“Chris was . . . aware of cultivating and managing his public persona,” said Peter Siegenthaler, a college classmate. “I think we all — certainly I — saw him headed toward the public side of public service.”

The son of a diplomat and an intelligence analyst whose childhood was spent all over South Asia, Van Hollen began his public-service career as a congressional aide, an expert in foreign affairs. “We grew up in a family that thought deeply about the role of politics and the importance of committing your life to public service,” said Cecilia Van Hollen, the congressman’s younger sister.

Chris Van Hollen was active in the anti-apartheid movement as a student at Swarthmore College. As a Hill staffer, he says, watching Sen. Richard G. Lugar (R-Ind.) organize votes to override President Ronald Reagan’s veto of sanctions on South Africa helped him “see elected politics as a vehicle for change.”

He ran for state legislature in 1990, driven by concern about overcrowded classrooms and underfunded schools in his home base, Montgomery County.

“We were both congressional staffers first who decided to run for office because we thought we could get something done,” said Heather Mizeur, who served with Van Hollen in the House of Delegates and is backing him in the Senate race.

Former colleagues describe him as eager to climb the ladder. He made it to the state Senate in 1995 by taking on incumbent Patricia Sher, the mentor who had brought him to Annapolis.

Van Hollen says Sher was out of step politically with her liberal district. Sher never forgave him for usurping her, saying that the challenge felt “like one of my sons has kicked me in the mouth with a boot.”

In 2002, he made the jump to Congress, beating favored Kennedy family member Mark Shriver in the Democratic primary and then defeating a well-liked Republican incumbent, Rep. Constance A. Morella, who had become vulnerable in a redrawn district.

“It was never a secret that he wanted to be in the U.S. Senate,” said Barbara Hoffman, a Van Hollen supporter who served with him in the state Senate. “He always was looking for what was going to be next.”

But Van Hollen did not jump at the first opportunity.

In 2005, then-Sen. Paul S. Sarbanes announced his retirement after 30 years, creating a rare open seat. Van Hollen, on his second House term, was intrigued. But he bowed to then-Rep. Benjamin L. Cardin’s seniority and the strong support Cardin had already amassed among state leaders and donors.

A decade later, when longtime Sen. Barbara A. Mikulski said in March 2015 that she would not seek another term, Van Hollen thought his time had come. He announced his candidacy two days later, immediately winning the endorsement of Senate Minority Leader Harry M. Reid (D-Nev.).

But Edwards, from a neighboring district and with five fewer years in Congress, did not recognize rank. She launched her own campaign, winning support from Emily’s List and other national progressive groups.

The poker of politics

Those who have worked with Van Hollen say he is a master at pushing past obstacles, linking common interests and finding compromise when needed to get a law passed or an agreement approved.

Though colleagues in Annapolis sometimes grumbled that Van Hollen was too invested in his own image, he proved adept from early in his career at marshaling the press to advance a liberal agenda.

In the state Senate, he secured money he was seeking for Montgomery County schools by teaming up with Hoffman, who represented Baltimore and was focused on allocating more funding to the poorest school districts.

“He was the most effective advocate for his constituency that I ever had to deal with,” Hoffman said.

Including more expensive school districts in the legislation, Van Hollen said, brought enough senators from those wealthier counties on board for the bill to pass.

“If you’re going to get stuff done, you’ve got to be willing to take a strong stand, and then you’ve got to know when to translate your leverage into results,” Van Hollen said. “It’s like how you play a poker hand.”

His preferred poker variation is guts — a deceptively simple game that offers high rewards for high risks.

Van Hollen’s combination of aggressiveness and obsessiveness impressed Minority Leader Nancy Pelosi (D-Calif.), who tapped Van Hollen to recruit Democratic candidates in 2006 and lead House campaign efforts for the next two elections. To her, he combined three key attributes: policy acumen, political smarts and people skills.

“He knows how to win elections,” she said.

Van Hollen helped Democrats take back the House in 2006 and expand their majority in 2008. Under President Obama, he helped write the Affordable Care Act and the economic stimulus package, which steered the country out of the 2008 recession. The 2010 elections were disastrous for Democrats, but Van Hollen distinguished himself within the party by raising enough money for candidates to compete.

Pelosi rewarded him with the Budget Committee post, which Van Hollen wanted because he said that in a Republican-controlled House, the action would be in blocking conservative economic plans and voicing alternatives.

“It’s a place where I think you really can at least set the framework for: ‘What do we stand for? What are our priorities as a country?’ ” he said.

Colleagues saw him as the perfect foil to Rep. Paul D. Ryan (R-Wis.), the Budget Committee chairman at the time. Van Hollen became a regular presence on cable news and the conduit between House Democrats and the White House. Pelosi said he was a natural choice to take part in bipartisan debt negotiations.

“He was one of us that was trying to get a solution,” said Rep. Fred Upton (R-Mich.), who served with Van Hollen on the debt-reduction “supercommittee” in 2011. “He’s well-respected on both sides and doesn’t take any cheap shots, and he works in earnest.”

Van Hollen also toiled on behalf of his constituents. Unlike most members of Congress, he insists that a senior staff person run his district office. He looks over nearly every piece of mail his staff sends out; if he recognizes a name, he adds a personal note.

“I’m not going to have anyone tell me I’m anything but better than Connie Morella” was his mantra early on, according to former chief of staff C.R. Wooters.

Bethesda resident Pat Talbert Smith says Van Hollen’s office spent more than a year making sure her father, a Tuskegee airman, was honored with a Congressional Gold Medal after he mistakenly was disqualified.

When her dad accidentally left an old photo of himself behind after the ceremony, Van Hollen mailed it to him, along with a note. The attention “means an awful lot,” Talbert Smith said. Especially because her father does not even live in Van Hollen’s district.

“Those are the kinds of things that Chris does all the time,” said Craig Rice, a Montgomery County councilman and longtime Van Hollen backer. He’s coined a name for them: “Chris-isms.”

Getting personal

In recent debates, the congressman struck a rare personal note, talking about the sex discrimination his mother faced while trying to get a job in the Foreign Service decades ago. But in general, he is more likely to pepper people with policy questions than share a family story or an emotional response.

On a trip to an innovative high school in South Baltimore, Van Hollen listened to three 11th-graders describe their love for the school. Then he pressed them to detail the policies that inspired that devotion. “How do you account for that better experience?” he asked.

The teenagers thought for a moment. The lack of bullies, they said.

He tried again. “Is there anything the school itself is doing?” he asked.

After Van Hollen failed several times to squeeze educational reform strategy out of the teenagers, an administrator stepped in.

On a walking tour through Baltimore’s troubled Park Heights neighborhood, Van Hollen only briefly mentioned his roots in the city. (His father and his paternal grandmother were active in local politics; Hollen Road, in the Cedarcroft neighborhood, is named for the family.)

“What I talk about is my efforts to listen to other people’s stories and translate those stories into action,” Van Hollen said. “What really matters at the end of the day are the stories of millions of Marylanders and how we can make a difference for them.”

Only if asked will Van Hollen discuss his love of fishing and biking, and his penchant for “spontaneous travel.”

During college, he and a friend hitchhiked across Alaska, earning money along the way at seafood-processing plants. Pressed to talk about the experience, he recalled that he started as a fish cleaner, before graduating to salmon grader and finally forklift driver.

In true Van Hollen fashion, he worked his way up.

Kelsey Snell contributed to this report.