Rep. Benjamin L. Cardin stood on the stairs inside a Chevy Chase supporter's home one night last week and touted his quick rise as a Senate candidate to those gathered below in the spacious foyer.

In just nine weeks, the Baltimore area lawmaker said, he has visited every region of Maryland. He has already raised more than $1 million for next year's race to replace retiring Sen. Paul S. Sarbanes (D). And he has won endorsements from numerous elected officials, including the dean of the state's congressional delegation, House Minority Whip Steny H. Hoyer of Southern Maryland.

Hoyer's backing, in particular, sent "a clear message," Cardin told members of the crowd as they sipped Chardonnay and nibbled on salmon, duck and asparagus hors d'oeuvres. "I'm the Democrat who's going to make sure we keep this seat."

Cardin insisted that his message of early momentum is not directed at anyone in particular. But interviews with some of his backers -- and the setting of Thursday night's fundraiser in Chevy Chase -- pointed to a prominent target: Rep. Chris Van Hollen of Montgomery County.

Van Hollen, a second-term House member with a reputation for embracing tough races, has said he will announce this month whether he will join the Democratic field. Besides Cardin, the race has already drawn former congressman and NAACP leader Kweisi Mfume and perennial candidate A. Robert Kaufman, both of Baltimore.

Although Cardin boosters say the race is winnable regardless of who else runs, his path to the nomination becomes more difficult -- and more costly -- if Van Hollen and others broaden the field. On the Republican side, Lt. Gov. Michael S. Steele probably will have no significant opposition if he moves forward with a Senate bid, party strategists say.

That dynamic should give pause to Van Hollen and other Democrats still looking at the race, said Montgomery Council member Michael Knapp (D-Upcounty), who attended Cardin's fundraiser Thursday but has yet to endorse a candidate. The event, held at the home of Jill A. Lesser, an America Online executive, drew several dozen prominent members of Montgomery's business, political and Jewish communities.

"The amount of effort and what he's accomplished in nine weeks have got to make others say 'Wow,' " Knapp said of Cardin's start. "I hope others will look at that. If we're going to spend a lot of time beating up each other in a primary, it's certainly going to benefit the Republican Party."

In an interview, Van Hollen said he was undaunted by Cardin's start, noting that he has $1 million sitting in his congressional account that could be used for a Senate bid. Shortly after Sarbanes announced his retirement in March, Van Hollen set up an exploratory committee to look at the Senate race and has since raised $700,000 before even declaring himself a candidate, he said.

"This has not been an idle exploratory period," Van Hollen said. "It's been a very active exploratory period. . . . I'm confident that if I get into this race, I will get in with broad support from across the Maryland community."

Van Hollen said he plans to use Congress's Fourth of July recess to ponder such issues as what impact "the wear and tear of a 15-month campaign" would have on his family.

Mfume, meanwhile, credited Cardin with "smart politics" during an interview.

"If the chairs were reversed, I'd be doing the same thing," he said. "The key is to make it appear that you can't be beat and deter others from getting in. . . . You try to create the impression that you're the flavor of the month."

Mfume, who launched his candidacy just days after Sarbanes's announcement, said he has raised about $150,000 since joining the race and has about $100,000 left from an old congressional account. He said he has focused more on connecting with voters and building a campaign organization than raising money.

Mfume's campaign has been hobbled by allegations of favoritism during his tenure at the NAACP. But some analysts argue that a decision by Van Hollen to enter the race could bolster his prospects by splintering the white vote.

Mfume remains a hero to many in the black community and is the only black Democrat in the race. Besides Van Hollen, other candidates considering a run for Sarbanes's seat include Joshua B. Rales, a wealthy Montgomery County businessman, and Anne Arundel County Executive Janet S. Owens. Both are white.

"I'm sure he'd like other competitors to get in," Matthew A. Crenson, a political science professor at Johns Hopkins University, said of Mfume.

Cardin has worked in recent weeks to demonstrate his appeal to black voters as well, though. His endorsements have included those of state Sen. Dolores G. Kelley, a veteran black lawmaker from Baltimore County, and the Rev. John L. Wright, a longtime pastor in Howard County and former chairman of the Maryland branch of the NAACP.

Many of the elected officials who have come out early for Cardin have known him for decades.

His political career began in 1966, when he was elected to the House of Delegates while in law school. Cardin gained statewide exposure during an eight-year tenure as House speaker, which ended in 1986 with his election to Congress.

"Sometimes you have to stop and hesitate and think through an endorsement," said state Sen. Philip C. Jimeno, one of 17 elected officials from Anne Arundel County who announced their backing for Cardin early last month. "That wasn't the case here at all. . . . Ben's earned it."

Quick-starting candidates sometimes stumble, however, and Cardin's opponents are hopeful that voters will not rely on early cues from elected officials once they tune in to the race. "This is still inside baseball," Mfume said. "The masses of people are not yet engaged in this election."

By his own admission, Cardin is not the most charismatic candidate. He is instead selling himself as an experienced lawmaker who has successfully pushed legislation in areas such as pension reform and health care. Although that might not be sexy by PR standards, Maryland elected Sarbanes, another cerebral legislator, five times.

"With me, you get a person who knows how to get things done," Cardin said at Thursday's fundraiser. "On Day One, you're going to get an experienced senator who knows how to deliver for the people of Maryland."

Rep. Benjamin Cardin has visited every region in Maryland and raised more than $1 million in nine weeks.