Maryland Lt. Gov. Michael S. Steele hosted the first major fundraiser in his as-yet-undeclared bid for U.S. Senate last night, attracting presidential adviser Karl Rove to headline a $1,000-a-person cocktail party in Washington.

The private affair was an attempt to introduce Steele to the ranks of national GOP donors who might not have encountered a man whose candidacy has become a top priority of the National Republican Senatorial Committee, the arm of the party that recruits candidates.

Steele said he was "very excited" to have captured the interest and backing of such national Republican luminaries as Rove. So too, it seemed yesterday, were his opponents.

Democrats dispatched about 35 protesters to the National Republican Senatorial Committee headquarters on Capitol Hill to heckle Steele. They blasted him for appearing with Rove, who has emerged as a central figure in the probe into the disclosure of CIA operative Valerie Plame's identity.

"No one who would use Karl Rove for a fundraiser is fit to represent Maryland in the U.S. Senate," said Tom Hucker, executive director of the advocacy group Progressive Maryland.

Democratic leaders said the event was evidence that Steele's run -- if it happens -- will be fueled not by a fire in the belly, or by a groundswell from the grass roots, but by the inside-the-Beltway GOP elite.

"There's no doubt the national Republican Party is orchestrating his campaign," U.S. Rep. Chris Van Hollen (D) said yesterday. "The event with Karl Rove demonstrates that better than anything else."

During an interview earlier in the day, Steele said he would expect nothing less from Democrats interested in derailing his campaign before it even starts. "There's a lot of 'gotcha' politics going on right now, both in the state and on the national level. But you take it for what it is," he said.

He said that although news outlets have written about the national figures who are lending him support, they are not reporting on the people he encounters during public appearances, even while running routine errands.

"They focus on the big names that you read about in the papers every day," Steele said. "But I listen to mostly the folks in the neighborhood, the folks in the barbershop, at the cleaners, the folks I see when I walk to the Giant to pick up some milk."

Steele initially declined to give out any information about the Rove event, even its time and location, but yesterday evening the GOP committee shared that about 65 people attended, donating about $75,000.

Neither Steele nor Rove stopped to address the protesters -- Rove waved to a photographer as he left the 90-minute event at the wheel of a Jaguar, with former RNC chairman Ed Gillespie in the passenger seat. One guest at the event, Maryland GOP Chairman John Kane, said Rove had joked to the attendees that he'd much rather see protesters hounding the Steele event than see them in front of Supreme Court nominee John G. Roberts Jr.'s house.

Maryland political analysts said Steele's ties to national Republican figures -- and Rove in particular -- could cut two ways for him if he chooses to run for the Senate seat opening up when Paul S. Sarbanes (D) retires next year.

In a state where John Kerry beat President Bush by 13 points and Democrats have maintained a strong majority of registered voters, the association may not be helpful, said Donald Norris, a government professor at the University of Maryland, Baltimore County.

"I would assume the Democrats are gleeful," Norris said of the Rove event. "I find it very, very odd that he would do something like this, knowing it will create a storm of controversy, especially when it's not necessary."

Storm of controversy might be an overstatement, but Democrats did mount an aggressive effort to publicize the event.

In addition to the protesters, Democrats circulated a mass e-mail from Kerry critical of the event and held a conference call with Larry C. Johnson, a former CIA agent and Plame classmate who has been one of Rove's most outspoken critics.

Johnson, a registered Republican from Bethesda, called on Steele to cancel the appearance with Rove, because, he said, "that kind of association is not what you want. . . . We don't need the Republican Party in Maryland tarred."

But James G. Gimpel, a government professor at the University of Maryland, College Park, said political calculations are different this early in a campaign, when a candidate's primary goal is to raise money.

"The main thing Michael Steele needs right now are the connections to the deep pockets," Gimpel said.

Steele is not expected to face competition for the GOP nomination. Three Democratic candidates have announced for Sarbanes's seat: Rep. Benjamin L. Cardin, former congressman and former NAACP leader Kweisi Mfume and Baltimore activist A. Robert Kaufman.

Staff writer Ann E. Marimow contributed to this report.