Five Black Democrats in the House of Representatives have endorsed Angela Alsobrooks in the party’s Senate primary in Maryland after her main opponent, Representative David Trone, used a racial slur in a House hearing.

The five representatives, all members of the Congressional Black Caucus, did not mention Mr. Trone’s use of the slur in their endorsements of Ms. Alsobrooks. But their support for Ms. Alsobrooks, first reported by Axios, over one of their House colleagues is notable, particularly given that the Democrats’ House leaders — Hakeem Jeffries, Katherine Clark and Pete Aguilar — have endorsed Mr. Trone.

Mr. Trone, a third-term representative from western Maryland, apologized on Friday after saying, in a House Budget Committee hearing, “This Republican jigaboo that it’s the tax rate that’s stopping business investment, it’s just completely faulty by people who have never run a business.”

He said in his apology that he had meant to say “bugaboo,” and added: “As an elected official, I have a responsibility for the words I use. Regardless of what I meant to say, I shouldn’t have used that language.”

A spokesman for Ms. Alsobrooks’s campaign confirmed the endorsements from Representatives Joyce Beatty of Ohio, Yvette Clarke of New York, Jasmine Crockett of Texas, Barbara Lee of California and Gregory Meeks of New York on Monday.

“These public servants know how important it is to have partners in the Senate who understand the challenges people face and are committed to working on real solutions, and I’m grateful to earn their support in this campaign,” Ms. Alsobrooks said in a statement.

Representative Jamie Raskin of Maryland also endorsed Ms. Alsobrooks on Monday.

Ms. Alsobrooks, the executive of Prince George’s County, is Black, and Mr. Trone is white. The primary between them and a number of lesser-known candidates is scheduled for May 14.

The winner is likely to face former Gov. Larry Hogan as the Republican nominee in a general election that became unexpectedly competitive when Mr. Hogan entered last month. While Maryland has not elected a Republican senator in more than 40 years, it elected Mr. Hogan as governor twice.

Several other representatives from Maryland have endorsed Ms. Alsobrooks, as has the state’s governor, Wes Moore.

A spokeswoman for Ms. Crockett confirmed her endorsement, and a spokesman for Ms. Lee confirmed hers. Representatives for Ms. Beatty, Ms. Clarke and Mr. Meeks did not immediately respond to requests for comment on Monday. Mr. Trone’s campaign also did not immediately respond to a request for comment.