BALTIMORE, MD - OCTOBER 07: Senator Ben Cardin (D-MD), left to right, Republican candidate, Tony Campbell and Independent candidate, Neal Simon are seen at the conclusion of a Maryland Senate debate at Fox 45 on Sunday October 07, 2018 in Baltimore, MD. (Matt McClain/The Washington Post)

Sen. Benjamin L. Cardin’s two main challengers criticized the two-term Maryland Democrat as too enmeshed in Washington partisanship during a feisty first debate Sunday that touched on issues as varied as education in Baltimore and Brett M. Kavanaugh’s confirmation to the Supreme Court.

Cardin, a third-generation Marylander who maintains broad support in the state, delivered a strong defense of his record, saying he is proud of what he has achieved for residents by working across the aisle. Cardin held a nearly 40-point lead in a Goucher College poll released last month, earning support from 56 percent of likely voters, compared with 17 percent for Republican Tony Campbell and 8 percent for Neal Simon, who is running as an independent.

“He is part of the problem,” Simon said of Cardin, adding that a vote for Cardin, who has represented Maryland in Congress for more than 30 years, is a vote for “more of the same.”

Cardin outlined his collaboration with Republicans in his closing statement, noting that he has worked to secure federal funding for the Chesapeake Bay with John Barrasso (R-Wyo.) and on international relations with the late senator John McCain (R-Ariz.)

“This is a tough environment,” Cardin said. “I’m going to fight to get Democrats elected in the midterms, but when the election is over, you’ve got to govern, you’ve got to work together.”

Cardin, who served in the House of Delegates for 20 years before being elected to Congress, said he was “not hiding” his long record in politics. The Cook Political Report, which rates congressional races, lists Cardin’s seat as “solid” Democratic, which is not surprising, given that registered Democrats outnumber registered Republicans in Maryland by a margin of more than 2-to-1.

“I think having background and experience is good,” he said in an interview following the debate.

Simon, a financial services executive from Potomac, said after the debate that he wants voters to be able to see “what a different government could look like, and what it might look like if we didn’t just have a senator following his party 97 percent of the time.”

Simon is on leave from his job as chief executive of Bronfman Rothschild as he campaigns across the state in an RV, trying to convince voters of the need for an alternative to the two-party system. He chairs the Greater Washington Community Foundation.

Cardin has raised over $4.2 million this election cycle, while Simon has raised $657,992 and loaned himself $525,000. Campbell, who won the nomination in an 11-way GOP primary, has raised $35,354.

Libertarian Arvin Vohra, who earned 1 percent in the Goucher Poll, is not accepting donations. Jerome Segal, a philosopher and progressive activist who ran against Cardin in the Democratic primary and is fighting in court to have his name placed on the ballot as an independent, raised $276,632 and took out a $1.3 million loan.

Neither Vohra nor Segal participated in the hour-long debate, which was held in WBFF-TV’s studio in Baltimore.

In his closing statement, Simon called for two more debates, which have not been scheduled.

He and Campbell, a political science lecturer at Towson University, delivered some of their sharpest criticisms in response to a question about Baltimore’s education system, which Campbell said suffers from a “lack of accountability.” Simon described Baltimore as a “city in decline” with an “unacceptably poor” public education system that Cardin should have done more to improve.

Cardin said he had done his best to “provide resources and demand accountability.”

The first question of the debate, which was moderated by WBFF-TV anchor Jennifer Gilbert, was about Kavanaugh, who was confirmed by the Senate on Saturday, mostly along party lines.

Cardin, who voted against Kavanaugh’s confirmation, said he worried that the judge will not be “an independent voice” on the Supreme Court. Simon said he would have voted against his confirmation but decried the “political circus” that the hearings became. Campbell, a conservative who voted for President Trump, said he would have supported Kavanaugh’s confirmation.

Campbell was the state chairman for Ben Carson’s 2016 presidential campaign and was appointed by Gov. Larry Hogan (R) to the state’s P-20 Leadership Council, which works on preparing students for the workforce.

He emerged as an occasional defender of Trump, saying “any other president” would have received a Nobel Peace Prize for such work on North Korea and declaring his support for a border wall.

Both Cardin and Simon said they appreciated Trump’s diplomatic overtures to North Korea and spoke about the need for comprehensive immigration reform.