Odetta, the famed American folk singer whose powerful songs became anthems for the U.S. civil rights movement, has died at 77.

Her manager, Douglas Yeager, said Odetta died of heart disease in a New York hospital on Tuesday.  Yeager noted she had hoped to sing during the inauguration of President-elect Barack Obama on January 20, when he is to become the first African-American
president of the United States.

Odetta sang during the 1963 march on Washington, which was led by civil rights leader Martin Luther King, Jr.  On that day, she performed a song from the slavery era called "O Freedom."

Odetta was a classically trained singer with an impressive voice that plunged deep and climbed high to deliver influential folk ballads and blues songs.  

In a 2007 interview with The New York Times, Odetta said she sang "liberation songs."  She told the newspaper that in an oppressive society, "you can either lie down and die, or insist upon your life."

She is credited with inspiring scores of artists, including Bob Dylan, Joan Baez and Janis Joplin.

Her work includes the 1956 album Odetta Sings Ballads and Blues, and the 1957 album At the Gate of Horn, which features the popular spiritual "He's Got the Whole World in His Hands."