Selma, Ala. ? Aging civil rights-era figures and a bipartisan congressional delegation walked across an Alabama bridge with a throng of thousands Sunday to commemorate the 40th anniversary of the Selma voting rights march that opened ballot boxes to blacks across the South.

Among those participating was Coretta Scott King, whose husband, the Rev. Martin Luther King Jr., led the historic march in 1965.

“The freedom we won here in Selma and on the road to Montgomery was purchased with the precious blood of many,” said King, who crossed the Edmund Pettus Bridge in a car.

Police estimated the crowd at nearly 10,000.

Others on hand to commemorate the march across the bridge included singer Harry Belafonte, who also took part in the demonstration 40 years ago, the Rev. Jesse Jackson, Senate Majority Leader Bill Frist, and Lynda Johnson Robb, whose father, President Lyndon Johnson, signed the Voting Rights Act into law in 1965.

“President Johnson signed that act, but it was written by the people of Selma,” said Rep. John Lewis, D-Ga., who was clubbed on the head during the “Bloody Sunday” attack on marchers by state troopers and sheriff’s deputies on March 7, 1965. He was among 17 blacks hospitalized as that march was turned back.

A second march two weeks later, under the protection of a federal court order and led by the Rev. Martin Luther King Jr., went 50 miles from the bridge over the Alabama River to the steps of the state capitol in Montgomery.

The attack and the march inspired passage of the Voting Rights Act, which barred obstacles such as literacy tests that were set up by segregationists to keep blacks from registering to vote.

A re-enactment of the five-day march is planned this week, culminating with a rally Saturday at the Capitol.

The Rev. Jessie Jackson, far left, walks with marchers Sunday on the Edmund Pettus Bridge in Selma, Ala.. At far right are the Rev. Joseph Lowery and his wife, Evelyn Lowery. Joseph Lowery joined the Rev. Martin Luther King Jr. on the march 40 years ago.

In a service at Brown Chapel, six blocks from the bridge, Lewis cited former President Bill Clinton, who crossed the bridge with Selma marchers in 2000, and former Alabama Gov. Don Siegelman as white politicians who have greeted modern civil rights concerns with open arms.

“Five years ago, this governor had all the state troopers line up on that bridge. Five years ago, state troopers, black and white, men and women, stood and saluted us,” Lewis said amid applause for Siegelman.

Certain provisions of the Voting Rights Act, such as the use of federal examiners and a requirement for Justice Department approval of election law changes, will be up for renewal by Congress in 2007.

Currently, 74 percent of voting-age blacks in Alabama are listed as voters. That compares with 77 percent of voting-age whites, based on figures compiled by the secretary of state and the Census Bureau’s estimates of voting-age residents.

In March 1965, only 19.3 percent of eligible blacks were registered in Alabama, compared with 69.2 percent of whites.