House Democrats chose Rep. Carolyn B. Maloney of New York on Wednesday as the next chairman of the Oversight and Reform Committee, a powerful panel that has participated in the impeachment investigation of President Trump and traditionally taken a lead role in scrutinizing the executive branch.

As the most senior member of the panel, Maloney has been serving as acting chairman since the Oct. 17 death of Rep. Elijah E. Cummings (D-Md.). But she faced a challenge from Rep. Gerald E. Connolly (Va.), who argued to his colleagues that he was better equipped to handle the rigors of impeachment and battling Republicans intent on protecting the Trump administration from scrutiny.

In the end, Democrats chose to respect seniority, electing Maloney on a 133-86 vote.

“I’m honored by this opportunity to do more for the American people and will do my best to follow the honorable example that Chairman Cummings left for us all,” she said in a statement Wednesday. “There’s much work to be done, and I can’t wait to get started.”

The race ended up as a two-member duel after several lawmakers bowed out, including Reps. Stephen F. Lynch (D-Mass.) and Jackie Speier (D-Calif.) — both veteran members of the panel.

As the most senior member on the Oversight panel, Maloney got a boost from key sectors of the Democratic caucus that prize the seniority system — including the 53-member Congressional Black Caucus.

“That is our tradition,” said Rep. Emanuel Cleaver II (D-Mo.), a former chair of the caucus. “It would not be in our interest to oppose seniority.”

Also playing to Maloney’s advantage were diversity concerns: Maloney is the only woman among the three committee chairs who have taken a lead role in the impeachment inquiry, alongside Foreign Affairs Committee Chairman Eliot L. Engel (D-N.Y.) and Intelligence Committee Chairman Adam B. Schiff (D-Calif.).

Connolly, 69, sought to target the record crop of House freshmen as well as fellow members of the sizable House delegation representing the Washington region. Connolly has represented a suburban district since 2009, after serving 14 years on the Fairfax County Board of Supervisors. He currently chairs the Oversight subcommittee on government operations, a panel with a broad jurisdiction over the federal workforce, the District of Columbia and more.

“My colleagues who have seen me take on Jim Jordan know I will not back down from a fight,” he wrote in a Nov. 13 letter to colleagues, naming the Ohio Republican who has served as Trump’s leading defender in high-profile hearings. “I’ve shown I have the skills to communicate our Democratic message while exposing the hollowness and contradictions of the Republican arguments.”

Maloney, 73, was able to overcome the implication of Connolly’s campaign pitch that she was not up to the job. While Maloney has chaired a Financial Services subcommittee and serves as vice chair of the Joint Economic Committee, she has not been closely associated with the Oversight panel’s recent work, and only began routinely participating in the impeachment investigation after Cummings’s death.

But she has also been able to point to a long oversight and legislative record dating to 1993, when she was first elected from her East Manhattan district. In recent years, she has been best known for her advocacy for 9/11 responders, pushing alongside other key lawmakers for permanent authorization of a federal victims compensation fund, as well as advocacy on Census issues.

“The situation being investigated as part of the impeachment proceedings is of the utmost importance, but we will not lose sight of the other ongoing investigations the Committee is conducting into the policies of the Trump Administration,” she wrote, citing the Department of Homeland Security’s practice of separating migrant families as they cross the border illegally, as well as “ethical violations by senior officials.”

Maloney’s election came after the House Democratic Steering and Policy Committee, a smaller group of Democrats heavily influenced by Speaker Nancy Pelosi (D-Calif.), chose Maloney over Connolly Tuesday night on a 36-16 vote.

In a tweet, Connolly congratulated Maloney and said, “we have a consequential responsibility in the next year to bring transparency and accountability to the Trump Administration for the American people, and Chairwoman Maloney has my full support.”

The pick by Democrats is likely to be formalized on the House floor Thursday, a senior Democratic aide said, speaking on the condition of anonymity to describe internal plans.