"President Johnson called the right to vote the lifeblood of our democracy. That was true then and it remains true today," Mr. Bush said in the first address of his presidency to the National Association for the Advancement of Colored People's annual convention.
"I look forward to the Senate passing this bill promptly, without amendment," Mr. Bush told the crowd, pausing as he was interrupted by sustained applause.
"So I can sign it into law," he finished, to more cheers.
Acknowledging his administration's bumpy relations with black voters, Mr. Bush said he wants to change the Republican Party's relationship with African-Americans.
"I understand that racism still lingers in America," Mr. Bush said. "It's a lot easier to change a law than to change a human heart. And I understand that many African-Americans distrust my political party.
"I consider it a tragedy that the party of Abraham Lincoln let go of its historical ties with the African-American community. For too long, my party wrote off the African-American vote, and many African-Americans wrote off the Republican Party."
Mr. Bush, joined by Secretary of State Condoleezza Rice and his chief political adviser Karl Rove, spoke as the Senate debated a bill to approve a 25-year extension of expiring provisions of the Voting Rights Act of 1965. The House has passed the bill, and the Senate was expected to pass it quickly, propelled by a Republican push to increase the party's credibility with minorities.
For five years in a row, Mr. Bush has declined invitations to address the NAACP convention. This year, he said yes. He was introduced by NAACP head Bruce Gordon.
"Bruce was a polite guy," Mr. Bush said. "I thought what he was going to say, 'It's about time you showed up.' And I'm glad I did."
Mr. Bush said he saw his attendance at the convention as a moment of opportunity to celebrate the civil rights movement and the accomplishments of the NAACP.
"I come from a family committed to civil rights," Mr. Bush said. "My faith tells me that we are all children of God — equally loved, equally cherished, equally entitled to the rights He grants us all.
"For nearly 200 years, our nation failed the test of extending the blessings of liberty to African-Americans. Slavery was legal for nearly 100 years, and discrimination legal in many places for nearly 100 years more."
A heckler, apparently protesting the Iraq war, briefly interrupted Mr. Bush's speech, CBS News reports.
Mr. Bush continued with his remarks as NAACP chairman Julian Bond rose to try to quiet the situation. Mr. Bush told Bond, "Don't worry about it. Don't worry about it."
The White House denied claims that Mr. Bush's appearance was a way of atoning for the government's slow response to Hurricane Katrina. The Rev. Jesse Jackson and some black elected officials alleged that indifference to black suffering and racial injustice was to blame for the sluggish reaction to the disaster.
Mr. Bush, noting that he has met several times with Gordon, and that they have discussed Katrina. "We've got a plan and we've got a commitment," Mr. Bush said. "It's commitment to the people of the Gulf Coast of the United States to see to it that their lives are brighter and better than before the storm."
Mr. Bush also recalled his visit in June to Elvis Presley's Graceland mansion in Memphis, Tenn., with Japanese Prime Minister Junichiro Koizumi. While in Memphis, the two made an unscheduled stop at the National Civil Rights Museum at The Lorraine Motel, where the Rev. Martin Luther King Jr. was assassinated in 1968. Mr. Bush and Koizumi emerged from a tour to stand on the spot on the motel balcony where King was slain.
They were joined by former NAACP head Benjamin Hooks.
"It's a powerful reminder of hardships this nation has been through in a struggle for decency," Mr. Bush said. "I was honored that Dr. Hooks took time to visit with me. He talked about the hardships of the movement. With the gentle wisdom that comes from experience, he made it clear we must work as one. And that's why I have come today."