BALTIMORE — A veteran congressman who voted against the war in Iraq, Rep. Ben Cardin, won the Democratic nomination to replace retiring Democratic Senator Sarbanes.

Mr. Cardin had edged out his closest competitor, former NAACP head Kweisi Mfume, and 16 other candidates and will face Republican Lieutenant Governor Michael Steele in November.

“I know that we are united,” Mr. Cardin told the Associated Press yesterday.”We [he and Mfume] ran a campaign that wasn’t about our election, it was about November’s election. We need to change the direction of the country. We had two people running who shared the same commitment.”

Mr. Cardin stopped short of declaring total victory, and Mfume did not concede the race.

“It’s how you finish — and we’re not finished!” a former congressman, Mr. Mfume, told volunteers, friends, and relatives. However, he acknowledged that victory was unlikely, saying Mr. Cardin would “be a damn good senator representing the state of Maryland.”

With 93% of precincts reporting, Mr. Cardin had 225,439 votes, or 46%, to Mfume’s 185,580, or 38%. The former head of the state GOP, Mr. Steele, faced little-known challengers Tuesday and cruised to victory with 87% of the Republican vote. Mr. Steele was the first black candidate elected statewide in Maryland. He spoke at the 2004 GOP convention, and President Bush and Vice President Cheney joined him at fundraisers. If he wins the general election, America would have two black senators for the first time; Senator Obama of Illinois is the fifth black senator in American history. The race between Mr. Cardin, who is white, and Mr. Mfume was amicable, with neither man criticizing the other and both voicing support for troop withdrawal from Iraq and universal health insurance.