While his main GOP rivals campaigned in Florida, Huckabee sat quietly through a nearly four-hour King ceremony at the Ebenezer Baptist Church. He was overshadowed by fellow Arkansan Bill Clinton, who received a long ovation for his 18-minute address.
The former president acknowledged Huckabee, who did not speak. "We don't agree on much, but he is a very good man," Clinton told the audience of several hundred.
Huckabee said he was willing to put aside campaigning for a half day to attend the King event, which he called inspiring.
The former Arkansas governor finished second in the South Carolina Republican primary over the weekend after campaigning in which he said the federal government should stay out of disputes over display of the Confederate battle flag in the state. He said last week, "If somebody came to Arkansas and told us what to do with our flag, we'd tell 'em what to do with the pole, that's what we'd do."
The flag is a symbol of racism to some, of Southern pride to others.
After his South Carolina loss, Huckabee needs strong showings in states such as Florida, Georgia and Alabama to keep his campaign alive. He went to Orlando for a late-afternoon rally and fundraiser Monday and planned to return to Atlanta Tuesday for an anti-abortion event.
"Winning Florida would be great," Huckabee told an Orlando airport crowd of about 100, speaking of the state's Jan. 29 GOP primary. But winning the nomination is the bigger goal, he said. "Nobody is going to have this wrapped up by Florida," he said.
"We plan on carrying Georgia," Huckabee told reporters.
After leaving the King ceremony, Huckabee was endorsed by three dozen African-Americans, most of them connected to conservative religious organizations.
Huckabee's strong opposition to abortion and gay marriage matches the "high moral values" of many black Americans, said William Owens, founder of a group called the Coalition of African American Pastors.