Thousands of workers from across the United States -- bus drivers, postal clerks, educators, longshoremen, farm laborers -- plan to converge Sunday on Washington to rally for jobs, universal health care and an end to the war in Iraq.

Organizers of the Million Worker March said they want to draw attention to problems facing workers in America and around the world, hoping to have their voices heard days before U.S. voters head to the polls to elect a president. They said labor unions of all sizes and trades, representing more than 3.5 million workers, have pledged support, from the Transport Workers Union in New York to the American Federation of State, County and Municipal Employees in Houston.

"Both union and nonunion workers realize that they're losing more and more every day," said Chris Silvera, 48, secretary-treasurer of Teamsters Local 808 in Long Island City, N.Y., which is sending three 40-seat buses of union members to Washington. "The fact is, neither party is really addressing the issues of the working class."

Though organizers said they expect tens of thousands, some pointed out that the "million" in the march title is intended to evoke the powerful imagery of the Million Man March in 1995, not to reflect a crowd count. Organizers estimated 100,000 on their permit application to the National Park Service.

"The Million Worker March is an expression of our intent to build a movement of that magnitude," said Ralph Schoenman of Vallejo, Calif., a march spokesman and member of the National Writers Union. "I can't predict that we'll have a million people at the march. I can say we expect massive numbers."

The AFL-CIO, the nation's largest labor federation, which represents more than 13 million workers, has not endorsed the event. It was the AFL-CIO that organized one of the labor movement's last major marches on Washington, a 1981 demonstration against Ronald Reagan's economic agenda that drew 260,000. AFL-CIO spokeswoman Lane Windham said that while the organization supports the goals of the Million Worker March, it is focusing instead on mobilizing voters. "This is an incredibly important election for working people, and we have to be very prudent about how we spend our resources," Windham said.

Silvera, with the Teamsters in Long Island City, said the AFL-CIO's decision undermines the labor movement and will affect the turnout Sunday. "I believe that we will be better than 150,000," said Silvera, a march organizer and chairman of the Teamsters National Black Caucus. "But you've got to understand that for every one I had there, the entire weight of the AFL was there to discourage 10 from coming."

Dozens of unions have endorsed the protest, but the idea for it came from a single local: International Longshore and Warehouse Union Local 10 in San Francisco. Clarence Thomas, 57, co-chairman of the national march committee and a crane operator on the Oakland docks, said Local 10 envisioned the protest as a response to attacks on working families from corporations, the Bush administration and Congress.

"Workers need to have their own independent voice, their own political vision, because no one can speak for workers but workers," said Thomas, a third-generation longshoreman.

Thomas and other organizers said much of the funding for the event comes from rank-and-file workers. One retired longshoreman from Local 10, Leo Robinson, has contributed more than $50,000, he said. "He is teaching us and showing us what it is going to take in the future to mount any kind of movement in the name of working people. We're going to have to do it ourselves," Thomas said.

Organizers have issued 22 demands, a broad array of grievances that go far beyond workers' rights. Organizers call for universal health care, a national living wage, guaranteed pensions for all working people and an end to the outsourcing of jobs overseas. They also are demanding a repeal of the Patriot Act, increased funding for public education, free mass transit in every city, a reduction of the military budget and cancellation of what they consider pro-corporation pacts such as the North American Free Trade Agreement.

The diverse demands have struck a chord with an eclectic mix of left-leaning causes. Anti-globalization groups such as San Francisco-based Global Exchange and environmental activists such as the Rainforest Action Network are backing the demonstration. A group of anarchists has called for an anti-capitalist feeder march but is urging participants to avoid confrontational tactics.

A Web site was created to help build antiwar turnout, and two of the major antiwar coalitions, International ANSWER and United for Peace and Justice, which have sponsored some of the biggest demonstrations against the Iraq war in Washington and New York, have endorsed Sunday's event. Many activists said this will be the last chance for a massive display of opposition to the war before Election Day.

" 'Money for jobs, not for war' is not just a slogan," said Larry Holmes, 52, co-director of the antiwar group International Action Center and a march organizer. "Now it's backed up with social reality. You've got working people there in large numbers who are saying it. . . . I think that will rock the powers that be."

The main rally is scheduled to begin at noon at the Lincoln Memorial. Following a number of speakers, including Martin Luther King III and Jesse Jackson, participants will gather in tents to discuss issues. There will not be a mass march, but a smaller solidarity march is planned to the Hotel Washington on 15th Street NW in support of District hotel workers, who are in the midst of contract negotiations. That march and the tent discussions are to begin about 3:30 p.m.