For the past two months, a long white van plastered with flyers, posters and banners has been cruising local neighborhoods blasting the speeches of Martin Luther King Jr. from its loudspeaker and raising the curiosity of Washington residents.

Nicknamed "the Freedomobile," the van carries a band of volunteers who knock on doors, distribute leaflets and implore strangers to participate in the 20th Anniversary March on Washington. On each of its sides a large black banner says in red letters: "Join the Jobs, Peace and Freedomobile."

The curious looking vehicle is on loan from the American Red Cross to the "Jobs, Peace and Freedomobile Project," a District-based grass-roots organization devoted to stirring support for Saturday's march.

For two months Freedombile volunteers have canvassed neighborhoods from the cobblestone streets of Georgetown to the hot, barren streets of Anacostia. With funding of less than $1,000, they have printed and distributed thousands of fliers and discussed the march with countless strangers.

"A lot of organizations are afraid to go door-to-door," said Damu Smith, 31, a community activist and founder of the project. "It might be easy to go downtown and pass out fliers at 16th and K streets. But you go to Valley Green, to the projects where people aren't working, and you ask them to come to a march. It's not easy. You have to be courageous."

The Freedomobile volunteers are blacks and whites, most of them in their 20s or early 30s, who vaguely remember watching the 1963 march on television as children.

Smith, a St. Louis native, said he organized the effort "to educate people about the issues around which the march is organized, to offer them some type of immediate service and to mobilize them for the march."

In addition to two small grants from American Friends Services Committee and the Commission For Racial Justice, the project has survived on "nickels, dimes and quarters people dug from their pockets, and money we raised from refreshment sales," Smith said. What has kept the volunteers going, they said, is the reaction of the people they've met.

Kay Shaw recalled walking into a steamy Anacostia laundromat, where women stopped folding their clothes, hushed their children and stepped away from their washing to encircle her and listen attentively.

"We passed out fliers along Martin Luther King Avenue in Southeast, and we turned around and drove back and there were no fliers on the ground," said Shaw, 30, an independent radio producer. "We went in shops and barbers said, 'Okay, let me put this poster in my window.' "

Smith said he was especially interested in Anacostia, an area he believes has been slighted by local government and other organizations. He set up Freedomobile's headquarters at the Malcolm X Cultural Education Center, 2208 Martin Luther King Jr. Ave. SE.

"When we went through Southeast playing Doctor King's 'I Have A Dream' speech, people flagged us down and asked for literature," Smith recalled. "Freedomobile is repeating what civil rights workers did when they journeyed to the South in the '60s.

At a festival Saturday in Alexandria, volunteers set up a health booth under shade trees and gave blood pressure checks, legal information and voter registration help as well as information on the march.

Volunteer Dennis Desmond, 31, a lawyer, has spent most of his weekends over the past two months passing out leaflets, giving free legal advice and begging people to attend the march.

"The last march made a tremendous impression on me," said Desmond, a member of the National Anti-Racist Organizing Committee. "One of the differences between the '63 march and today is that the last march brought about legal changes. Now that we've dealt with that, we're in a position to have some real gains."

Smith, who recently worked as a civil rights monitor for the American Friends Service Committee, got the idea for Freedomobile last February during a meeting of the local chapter of the national Coalition of Conscience, which is organizing this year's march.

"I felt the pace for getting out in the community was a little slow," Smith recalled. "In order for people to get informed, we needed to move faster than the coalition was moving at that time . . . we needed a different approach.

"The emphasis then was on going to the heads of labor groups, the heads of churches, the heads of this and that," he explained. "I felt it was important to mobilize at the grass-roots level."

He asked friends to join him, and among those who did was Shaw and Dr. Mcheko Graves, 28, a resident in psychiatry at St. Elizabeths Hospital. Graves, one of the national coordinators for the medical-aid support unit for the march, has worked with Freedombile volunteers in their health booths.

"A lot of people said, 'I can't afford to go to a doctor.' This is how Reagan cuts have hurt health care. People can't get decent health care unless they have jobs," Graves said. She said she is participating in the march because "health care is treated as a commodity now, rather than as a right."

"Even if people don't come to the march," Smith said, "we have educated them on the issues involved, and we have provided them with a service."