Thirty minutes before the vote, Sen. Edward T. Conroy was still juggling, still trying to piece together a winning majority. Huddled in his Senate office with his closest allies today, he took stock of the few jobs he had not already promised and set out for a last-minute lobbying effort on the Senate floor.

The moment he reached the marbled Senate chambers, Conroy discovered that his campaign for presidency of the Maryland Senate was lost. Sen. Thomas P. O'Reilly, a member of Conroy's Prince George's County delegation, told him he was planning to shift his support to Sen. James Clark Jr., assuring Clark enough votes to win.

Clark's victory in the Senate, coupled with the less climactic, uncontested election of Baltimore Del. Benjamin L. Cardin as speaker of the House of Delegates, elevates to the highest legislative leadership positions two men known for their support of progressive legislation and their political independence.

The elections took place free of the influence of the governor's office fot the first time in years, symbolizing a new degree of independence for the legislature after years of strong executive control under suspended Gov. Marvin Mandel.

Four years ago, Mandel all but handpicked the last group of legislative leaders, bypassing Clark who was vying for the Senate presidency. This time around, Harry R. Hughes Hughes made a point of staying away from the leadership fight, saying he believed it was up to the legislature to organize itself.

Cardin, 35, a Baltimore lawyer from a prominent political family, and Clark, 59, a dairy farmer who lives in Howard County, are expected to use their new independence in different ways. Cardin plans to play an active role in the shaping of legislation, while Clark is expected to serve as a mediator and traffic cop who focuses on moving bills along rather than initiating.

The contrast between the Senate and House deliberations could not have been sharper.

Clark's election in the Senate, with all its traditions of decorum and statesmanship, came at the end of an old-style political catfight that saw several senators refusing to commit themselves while weighing the candidates' promises of choice committee assignments. At the same time, the two candidates -- Conroy, in particular -- were making those promises wherever they could sense a vote for their side.

Conroy, a veteran senator who chairs the Constitutional and Public Law Committee, was busy promising a chairmanship here and leadership post there up to the moment he learned of O'Reilly's defection and, with it, his defeat.

As late as this morning, Conroy had attempted to swing three votes by offering the majority leader post to Sen. Rosalie Abrams, the chairmanship of the Intergovernmental Affairs Committee to Sen. Clarence M. Mitchell III and a vice chairmanship to Sen. John Carroll Byrnes.

Although Conroy said he was merely following a normal method of courting votes, the frenzy with which he went after support eventually disturbed some of his closest supporters. "At this point, I don't really care if Ed gets it," said fellow Prince George's Sen. Thomas V. (Mike) Miller shortly before the caucus. "He's made so many deals it doesn't mean anything anymore."

Miller was still prepared to vote for Conroy, something that all eight Prince George's senators had pledged to do weeks ago. But O'Reilly, who has always been somewhat of a loner and maverick in Annapolis, decided to scrap the pledge and vote for Clark, explaining that he was upset by the special interests lobbying on Conroy's behalf.

"I said I would vote for Conroy as long as he was a viable candidate, "O'Reilly explained after the session. "When I saw him wheeling and dealing for votes it convinced me that he was not viable."

Conroy and some of his allies were visibly shaken by O'Reilly's last-minute switch, but their anger did not stop them from conceding the presidency to Clark with a sudden profusion of goodwill and conciliation. In a concession speech, Conroy spoke of the "courage to withdraw." His compatriot from Prince George's, Sen. Peter Bozick, said Conroy's withdrawal served as "an example of self-sacrifice for the nation."

As Conroy set modestly at his desk, Boizck compared him to the Charles Dickens character who uttered, on the way to the guillotine, "Tis a far, far better thing I do..."

In the House, a body rarely known for its orderliness, the election of Cardin as the youngest speaker in Maryland history was carried out with all the drama and suspense of a group of stockholders reelecting the chairman of the board. His election was uncontested and came, as he had said it would for several months, without one promise to his fellow delegates.

"Ben didn't tell anyone who he would appoint to what," said Del. Gerard Devlin (D-Prince George's). "He's so well respected that he wouldn't have had to do it even if he wanted to, which he didn't. We've just elected the most open and unfettered leader in history."

Cardin, had been quietly lining up support for the position for several years and began actively pursuing it six months ago when Speaker John Hanson Briscoe announced that he would not seek reelection. He had earned the respect of most House members in recent years for his smooth handling of the powerful Ways and Means Committee and his knowledge of tax measures.

While Cardin's election went uncontested, a 30-minute debate that preceeded it gave the 53 new delegates a fitting introduction to the House. There was Montgomery Del. Donald Robertson (D), who is interested in procedure, pushing through a set of rules for the caucus; Del. Charles Blumenthal (D-Prince George's), intested in everything, attempting to make sure the uncontested election would be conducted by secret ballot, and Del. Charles Krysiak (D-Baltimore) walking out of the room muttering: "I gotta get out of here. I gotta get a judgeship."