WASHINGTON – Supporters for Senators Obama and Clinton staked out competing positions today as Democrats searched for a compromise to seat disputed convention delegations from Florida and Michigan and clear the way for a smooth end to the marathon struggle for the presidential nomination.

In the opening hours of a daylong meeting of the party’s Rules and Bylaws Committee, Mrs. Clinton’s designated spokeswoman urged the panel to grant a full vote for each of Florida’s 211 disputed delegates.

“In life you don’t get everything you want. I want it all,” a Florida state senator, Arthenia Joyner, said with a smile.

But moments later, Mr. Obama’s campaign called for half-votes for each of the 211. Rep. Robert Wexler of Florida said that marked an “extraordinary concession, in order to promote reconciliation with Florida’s voters.”

Obama supporters cheered loudly when he spoke, but there were boos from some in the audience who back Mrs. Clinton.

The challenge is to “come together at the end of the day and be united,” the party chairman, Governor Dean, told members of the committee gathered at a hotel across town from the White House.

Mr. Obama is a mere 42 delegates short of the 2,026 needed to clinch the nomination, in the Associated Press tally, and appears on track to wrap up the party prize in the coming days. He intends to signal the beginning of his general election campaign next Tuesday by holding a rally in the arena in St. Paul, Minn., where Republicans are staging their convention this summer.

Mrs. Clinton, who picked up the support of a Louisiana super delegate during the day, trails her rival by about 200 overall. She has pressed to have the entire Michigan and Florida delegations seated, both to narrow the gap and to buttress her claim that she has outpolled her rival in the popular vote in the primaries and caucuses.

If anything, the Michigan case was more complicated than the one in Florida. Mr. Obama’s name was not on the primary ballot. Mrs. Clinton prevailed over “uncommitted” and Mr. Obama’s allies claim the large majority of those votes were cast by his supporters.

The state party chairman, Mark Brewer, urged the panel to award Mrs. Clinton 69 delegates and Mr. Obama 59 — an allocation that neither candidate has endorsed publicly.

Mrs. Clinton campaigned in Puerto Rico as the committee met, hoping for a strong showing in tomorrow’s primary. Mr. Obama was in South Dakota, one of two states holding elections on Tuesday, the final day on the primary calendar. Montana is the other.

Numerous potential compromises have been discussed in recent days to ease the controversy over Michigan and Florida. All of them would allow the former first lady to draw closer to her rival without threatening his hold on the nomination.

Several hundred protesters maintained a noisy but peaceful presence on the sidewalk outside the hotel where party activists met.

Beverly Battelle Weeks, 56, said she got up before dawn to make the drive up from Richmond, Va. for the rally. She carried a black umbrella on which she had pasted letters spelling out “Count All Votes.”

“The right thing to do is to seat all the delegates. Anything less is not democratic,” she said.

Michigan and Florida both held primaries in January, earlier than party rules allowed, resulting in the disqualification of their delegates.

Alexis Herman, who heads the rules committee, called that the “maximum penalty,” an understatement given the controversy it has caused in the epic battle between a woman and a black man for the nomination.

In all, there were 368 delegates in limbo.

That totaled 211 from Florida, including 185 who would have been elected if the primary had counted, and an additional 26 superdelegates, who are party leaders. For Michigan, the breakdown was 128 delegates who would have been elected if the primary had counted and an additional 29 super delegates.

“We have suffered horribly,” a Democratic National Committee member from Florida, Jon Ausman, said. He recommended that the rules committee give all his state’s superdelegates a full vote at the convention and grant one-half vote to the rest.

Moments later, a Clinton supporter, Senator Nelson of Florida, urged a full vote for all 211 of the state’s delegates. He said nearly two million Democrats voted in the disputed primary, adding that they “violated no rule. Yet they are the ones who would be unfairly punished. And they do not deserve punishment.”

At the same time, he seemed to say he supported Mr. Ausman’s proposal for something less than his own proposal.

The most widely discussed compromise envisioned granting seats to all the state’s delegates, but giving each one-half a vote. If so, the number of delegates needed to clinch the nomination would rise from 2,026 to 2,118.

That would satisfy Mrs. Clinton’s call for all to be seated without jeopardizing Mr. Obama’s lead.

Both candidates were amply represented around the hearing table, with numerous supporters holding seats on the committee.

Mrs. Clinton won the Michigan primary January 15 and the Florida vote two weeks later after all the candidates agreed not to campaign in either state.

At the time, she said the vote did not matter. But once she fell behind Mr. Obama in the delegate competition, her position shifted.

While Mr. Obama initially showed no enthusiasm for seating the two delegations, he has shown more flexibility in recent weeks — as long as any compromise left his status as front-runner unchanged.