One day in the late 1950s, Dorothy F. Cotton, a graduate student, was picketing a Petersburg, Va., dime store where blacks weren't allowed at the lunch counter. The civil rights movement was beginning, and Cotton was part of it. But as she marched, an old black man taunted her: "Lady, what you doing walking in front of that store? Ain't you got a table at home?"

Cotton was stunned. "I put down my picket sign and talked to him. I said, 'How do you feel when your wife goes to the dime store but has to go back home if she wants a cup of coffee?' I realized he really didn't understand why we were in the streets. I felt really motivated to take time and talk to him. I told him, 'This is the only way we can call attention to this injustice.' "

It was Cotton's first memorable experience as an educator of the black American electorate -- a job that was to absorb her through the explosive years of the civil rights movement. As education director of the Rev. Martin Luther King Jr.'s Southern Christian Leadership Conference from 1960 to 1973, Cotton ran the Citizenship Education Program that trained more than 8,000 blacks in political participation, voter registration, constitutional rights and nonviolent protest.

She became a close associate of King and an important figure in the movement, but Cotton never forgot that old man in Petersburg and how he had been "brainwashed" by a racist system to believe that blacks should do nothing to upset "white folks." Many of her students, who came from all over the South, were uneducated people, but they were leaders in their communities and they returned home from Cotton's five-day workshops to teach classes of their own.

The SCLC workshops -- most of them held in a schoolhouse in McIntosh, Ga., where slaves had once gone -- were part of the beginning of the massive voter registration and education drives that were to transform American society generally and the political landscape of the South in particular.

"The civil rights movement that brought a revolution to America, it did not emanate from the halls of the Harvards and Cornells," Cotton told a packed auditorium at the Smithsonian's Museum of American History this weekend. "It came from simple, unlettered people. They started to stand tall, to march, to demonstrate. They were going to appropriate it for themselves."

Her speech was electrifying. A short, energetic woman with copper-colored hair and a high-pitched speaking voice, she began by looking out at the audience -- about half black and half white -- and saying, "Gee, what a beautiful sight. You know why? All colors, shapes and faces!"

Then she said, "We're gonna just do it. So let's pray!"

And in a ringing voice she began singing, "Come by here, my Lord. Oh Lord, come by here."

The audience immediately joined in, singing loudly and un-self-consciously. You could see why singing was an integral part of the Citizen Education Program -- "to motivate people, so they would feel a little revved up," as Cotton put it.

Later in the program she was joined by the original Freedom Singers of the Student Nonviolent Coordinating Committee -- Rutha Harris (whose voice has been described as "a force of nature"), Bernice Johnson Reagon (now the leader of Sweet Honey in the Rock), Charles Neblett and Cordell Reagon. They sang "Keep your eyes on the prize" and "Ain't gonna let nobody turn me 'round" and by the end the whole audience was holding hands and swaying and singing "We Shall Overcome."

In her workshops, Cotton said, singing was interspersed with civics lessons, even spelling lessons. People would learn how to spell A-M-E-N-D-M-E-N-T or M-A-Y-O-R and they would sing it as they spelled it. Then they would talk about what it meant.

"The songs helped to keep us from feeling lost," said Cotton. They helped her work with people "right off the farm and plantation who could barely read or write," to explain to them, for example, their right to assemble and to petition for a redress of grievances.

People made amazing breakthroughs.

Cotton remembered an old woman whose son was trying to explain "citizenship" to her. This son's "daddy was so afraid of white folks, the scars were so deep, he bought a car" but wouldn't return to the dealer to have it repaired because he "didn't want to bother the white folks."

Nevertheless, the son talked to his mother until one day she saw it. Suddenly saw everything clearly, just like that.

And she said: "The cobwebs come jus' a-movin' from my brain."

Cotton closed her eyes and said the words slowly. Savoring.

The cobwebs come jus' a-movin' from my brain.

When Cotton started her work, there were only 78 black elected officials in the entire South, according to Linda Williams, associate research director at the Joint Center for Political Studies, a black research organization. Today there are 6,681 black elected officials in America, including 303 black mayors -- two-thirds of them in the South.

That's still only 1.4 percent of all elected officials in the country, but voter registration statistics suggest the possibility of further change. In 1964 in the South, 52 percent of blacks were registered, compared with 61 percent of whites. But by 1986, Williams said, black registration in the South outpaced white registration for the first time, 65 to 63 percent.

Washington Post-ABC News surveys taken in late 1987 show a difference of less than 1 percent between black and white registration nationally. Black voters helped return Democrats to power in the U.S. Senate in the 1986 election by voting to unseat incumbents in such states as Alabama, Georgia and North Carolina. Black voter turnout was in excess of 85 percent in those races, according to Sonia R. Jarvis, executive director of the National Coalition on Black Voter Participation.

"And people like Mrs. Cotton deserve a lot of credit," Jarvis said.

Cotton, in an interview after her Smithsonian speech, said she thinks the presidential candidacy of Jesse L. Jackson is a strong encouragement for black registration today. Jackson is the only candidate actively pushing registration on the stump, and "the fact that he's running itself motivates a lot of people," Cotton said. "Jesse Jackson's campaign is a result of the civil rights movement. It's another chapter, another stage of the struggle to set things right."

Now the director of student activities at Cornell University, Cotton came up the hard way. She was the second of four girls; her mother died when she was a child; her father was a laborer in a tobacco factory in Goldsboro, N.C.

"We never had a book in my house," she said. "Dad didn't know what college was, actually." But with encouragement from her high school English teacher, Cotton got a small scholarship and attended Shaw University in Raleigh. She worked three jobs and became a "surrogate daughter" to the college president and his wife. When he moved to Virginia State College in Petersburg, not far south of Richmond, Cotton went with the family.

There she became involved in civil rights protests inspired by the Rev. Wyatt T. Walker, who was to become a key figure in the SCLC. At Walker's house she first met Martin Luther King. "I remember seeing him sitting there at the dining room table, and he seemed a very simple, humble, unassuming person. That impression never left me."

In September 1960, after Cotton had married and received a master's degree in speech therapy from Boston University, her husband drove her to Atlanta, where she intended to work at SCLC for six months or so. She stayed more than a decade. Her husband remained in Virginia, and eventually they were divorced.

In Atlanta, she said, "The movement became my whole life. I didn't think in terms of hours. We'd meet all night sometimes in the middle of demonstrations. Personal life, social life, everything just flowed right together. We became a family." Besides running the education workshops, Cotton participated in most of King's demonstrations and other activities until his murder at a Memphis motel on April 4, 1968.

When he flew to Oslo in 1964 to receive the Nobel Peace Prize, Cotton was in the entourage of about 30 who accompanied him.

"I remember Dr. King's mother {Alberta Williams King} on the plane. We were flying as the sun was coming up, her singing a song, 'Oh day yonder, come day.' And everybody was singing, 'Day done broke into my soul,' and Dr. King stood up and sang on the plane. It was joyful ... I remember being overcome and crying in the ceremony, all dressed up in my new rose-colored satin suit. Dr. King made his Nobel speech, and they played the music from 'Porgy and Bess,' and I heard that music and I just cried. And I realized the reason I cried and was so overcome was that just days before we had been in Birmingham in our demonstration clothes with the dogs and fire hoses. And there we were in Oslo, wined and dined by the queen."

Cotton had been with King in Memphis, but had returned to Atlanta early in the afternoon of April 4. She was taking a nap in her apartment when a woman from another apartment woke her up and said, "Dr. King's been shot. Somebody killed him."

Cotton was numb. She said nothing. "I got dressed and it was just dusk, dark, and I got out of the house, got in the car and started driving to Sunset Avenue, where Dr. King's house is. And I remember when I looked up and saw many police cars with lights flashing and lots of cars in the street, I remember screaming in the car."

Afterward, "We were really in mourning for two or three years. We worked on the Poor People's Campaign in this terrible state of mourning ... When that was over I went back to Atlanta and was trying to continue to run the Citizenship Education Program."

She ran it for three more years before it began "winding down." Then she went to Birmingham to direct a Head Start program there.

Now, at Cornell, she tries to convey her experiences to the younger generation, both black and white.

"You must have a dream," she tells the kids. "You must care about what's not working right in our society. You must develop a vision of what kind of world you want to live in."