(CNN) -- Attorney General Eric Holder joined NAACP leaders on the steps of the South Carolina Statehouse in Columbia on Monday, with the Confederate flag fluttering overhead, to promise he will aggressively protect federal voting rights for minorities.
NAACP National President Ben Jealous said he had chosen to be at the Columbia ceremonies honoring the Rev. Martin Luther King Jr., declaring South Carolina is "ground zero" in the battle for African-American voting rights.
As the NAACP speakers denounced the banner of stars and bars that the state continues to display, Holder focused on defending provisions of the Voting Rights Act that he claims are under assault by South Carolina.
The Justice Department has refused to grant the needed approval of a law passed by the legislature requiring most voters to present a government-issued photo ID at the polls.
"After a thorough and fair review, we concluded that the state had failed to meet its burden of proving that the voting change would not have a racially discriminatory effect," Holder said.
The Justice Department has also sued South Carolina, challenging its law designed to curtail illegal immigration in the state. The government has moved to block laws in six states, including Arizona, which has taken the issue to the Supreme Court. The ruling expected by this summer will likely affect South Carolina.
Holder said the Justice Department is continuing to review proposed redrawing of congressional and legislative districts in South Carolina.
The Columbia rally Monday featuring Democrats was a rare aside from the Republican pre-primary fever gripping South Carolina, which has grabbed virtually all of the media attention as the presidential candidates jockey in advance of Saturday's primary. Five GOP candidates remain in the running, with four of them hoping to catch leading candidate Mitt Romney in the final days of the campaign.
There is no Democratic primary election.
Holder made no mention of the GOP race, but drew applause from the largely African-American crowd when he invoked the name of his boss, President Barack Obama.