Donna Edwards and Chris Van Hollen are having their first debate on Friday. (AP Photo/J. Scott Applewhite, File) (TWP/TWP)

The two Democrats battling for a rare open Senate seat in Maryland hit each other hard Friday in the first debate of the primary season, with Rep. Chris Van Hollen describing Rep. Donna Edwards as dishonest and ineffective, and Edwards calling him an establishment figure who is out of touch with everyday voters.

The hour-long radio debate, hosted by WAMU’s Kojo Nnamdi and Tom Sherwood of WRC-TV (Channel 4), was the first time the candidates had engaged each other directly in a contest that will probably determine who represents Maryland in the Senate for decades to come.

The high stakes were clear in the testy exchanges between the lawmakers, who share similarly liberal voting records and policy positions. With little to debate in terms of issues, the candidates focused on effectiveness and background.

Van Hollen, 57, a member of Congress since 2003, said that as the top Democrat on the House Budget Committee, he has led the fights that Edwards only talks about. Edwards, who became a member of Congress in 2008, said she is a more consistent voice for working families.

So far, Edwards, also 57, more often has been the one to go negative, painting Van Hollen as too quick to compromise with Republicans. During the debate, however, Van Hollen was the prime aggressor. He said the congresswoman’s criticisms were essentially lies told to cover her weak record.

Rep. Chris Van Hollen (D-Md.) meets with local community partners of the Benjamin Franklin High School at Masonville Cove during a campaign stop in Baltimore. (Amanda Voisard/For the Washington Post)

“Ms. Edwards has not been telling Maryland voters the truth,” Van Hollen said. He accused her of “a lot of rhetoric but no results, no record.”

Most polls this year have shown the candidates essentially tied. But a poll by the Baltimore Sun and the University of Baltimore from last week had Edwards six points ahead. The primary is April 26.

Three times during the debate, Van Hollen invoked The Washington Post Editorial Board, which in its endorsement of Van Hollen called Edwards “notorious for inattention to constituent services and teamwork.” He said that Edwards’s constituents call Van Hollen’s office because she fails to help them.

Edwards needled Van Hollen back, attacking his past support for free-trade agreements, budget negotiations based on a framework that included cuts to Social Security and proposals that he backed in the Maryland legislature to strengthen criminal sentences.

“I really have to question whether he has the capacity to deliver on criminal-justice reform,” Edwards said. “Marylanders are tired of career politicians willing to trade away our values just to get a deal or get a headline.”

She also made a forceful case that voters should consider her personal history and perspective as a black single mother before deciding who should replace retiring Sen. Barbara A. Mikulski, the longest-serving woman in Congress.

Rep. Donna Edwards (D-Md.) campaigns in Cambridge, Md. (Jabin Botsford/The Washington Post)

“I think race does matter,” Edwards said. Noting that there are only 20 women and two African Americans in the Senate, she said, “It is time that we had the ability to speak for ourselves.”

Van Hollen pointed out that Edwards is not co-sponsoring either of two congressional bills that would attack mandatory minimum sentences. He accused her of taking credit for bills that she had failed to even vote on.

“I wish she would join me in co-sponsoring the legislation so she would actually get some of this work done,” he said.

While she attacks him for being close to Wall Street, Van Hollen said he was “literally leading the fight” to close tax loopholes and better regulate the financial industry.

When Edwards criticized her opponent for agreeing to compromise with the National Rifle Association in a campaign-finance bill, the congressman said he was “the only candidate here who has taken on the NRA and won.”

Edwards pushed back, saying she was proud of her record and had worked across the aisle on science, transportation and education legislation.

“Mr. Van Hollen is completely off base,” she said. Attacking her for missing a recent meeting with Mikulski and Gov. Larry Hogan (R) was “ridiculous,” she said, because Van Hollen had missed similar events.

Edwards dismissed the endorsements Van Hollen held up as evidence of his superior skills. “It is no surprise to me that the political establishment endorses the political establishment,” she said. “It is no surprise to me at all.”

As in a fundraising email this week, she hammered state Senate President Thomas V. Mike Miller Jr. (D-Calvert) for saying that Van Hollen was “born to the job.”

“I have walked in the shoes of the people I hope to represent,” she said, recalling that she was the first in her family to go to college and got through law school while raising an infant son.

Van Hollen said the support he has won from all across Maryland cannot be dismissed simply as the “establishment.”

“These are people who have worked with both of us, and these are people who can testify to results,” he said.

The clashes continued Friday evening at a candidate’s forum in Greenbelt that drew a capacity crowd. At one point, several Edwards supporters reacted angrily when Van Hollen addressed his opponent as “Ms. Edwards” rather than “Congresswoman,” prompting a baffled response from the lawmaker. The candidates interrupted each other, with Edwards twice interjecting as Van Hollen attacked her record.

“Does anybody really believe that I’m in the tea party?” she asked when Van Hollen pointed to a vote of hers with Republicans against a debt deal.

When he brought up a group of employees from NASA that has accused her of ignoring complaints of racism there, she stood and cut in to say that she had been working on the issue for a year and the group simply didn’t get the result they wanted. “I worked at NASA, I think I know something about it,” she said.

Edwards again emphasized her particular perspective, saying she knows what it’s like to live under student debt and talk to her son about dealing with the possibility of racial profiling by police. Van Hollen again countered that he has been more effective than she has in dealing with specific issues.

“I didn’t have a family member who was a victim of gun violence,” he said, but he worked to pass gun safety legislation while a state legislator.

Several Republicans are running for their party’s nomination for the Senate seat, including Del. Kathy Szeliga (Baltimore County), the minority whip in the House of Delegates. But both Van Hollen and Edwards have higher profiles in the state and more impressive political résumés.

The person who gets the Democratic nomination will face the winner of the Republican primary in November. With registered Democrats outnumbering registered Republicans in Maryland by more than 2 to 1, the Democratic nominee will be the overwhelming favorite.