Harris headlines an annual event sponsored by the NAACP, the nation's oldest civil rights group, which includes a prayer service and a march to the South Carolina State House in Columbia. There, Harris will press one of Democrats' central election messages - Biden and Democrats will protect all Americans' rights.

"She'll talk about the full-on assault on fundamental freedoms that we're seeing across the country," including reproductive rights, said a person familiar with the speech Harris plans to deliver.

U.S. President Joe Biden is also expected to mark the holiday by participating in a "service event" in Philadelphia, Pennsylvania, a state his aides regard as must-win in November. Republicans, including that party's front-runner former President Donald Trump, are wrapping up their Iowa campaigns on the day of their first nominating contest.

Biden also planned to call into a syndicated radio show hosted by Black civil rights advocate Rev. Al Sharpton on SiriusXM during the afternoon, according to the show's producers.

Meanwhile, Harris, the country's first Black vice president and its highest-ranking Black and Asian elected official, is tasked with outreach to people of color and younger voters, groups whose support for Biden has waned.

Long the Democratic Party's most reliable backers, these voters are wavering over economic anxiety and policy disappointments in divided-government Washington. Echoing other recent public-opinion polls, a Economist/YouGov survey this week found only 67% of Black U.S. adults had a favorable view of Biden.

Once a major global port for slaves, South Carolina is where the first volleys of the U.S. Civil War were launched in 1861. Under post-war Jim Crow laws, the state's schools and public facilities were segregated through law and intimidation, while Black people were largely excluded from voting and serving in elected office.

The movement associated with King, the NAACP and others used non-violent protest and public pressure to overturn the Jim Crow system.

Still, economic inequality remains pronounced, as in much of the United States. Six decades after the federal government started forcing South Carolina to end legal segregation, some 24% of Black residents in the state live in poverty, compared to 10% of White South Carolinians.

It was not clear how Republican candidates would mark the MLK holiday during the Iowa caucus. The Trump campaign and the Republican National Committee (RNC) did not respond to requests for comment; a RNC official told the AP last year the overlap between caucus and the holiday was an oversight.


Biden put South Carolina first in the party's nominating schedule this year, elevating a state where more than half of Democrats are Black and all but shutting out a serious primary challenge.

Democrats hold their primary here on Feb. 3, followed by Republicans on Feb. 24.

The president's triumph in the state's 2020 Democratic primary rescued a broke and flailing campaign, convincing rivals that no one could match his strength with the Black voters who vote 9-to-1 for the party in national elections, a larger share than any other ethnic group.

More than a quarter of the state's population is Black, about twice the national average.

Now, Biden wants an overwhelming win here over long-shot challengers to quiet doubts about his re-election bid, which has been plagued by voter concern over the economy, the country's direction and his age, 81. Trump is 77.

Lachanda Reeves Canty, 48, of Columbia, said Biden's age is a concern not because of his ability to do the job but because he brings the perspective of an older man to challenges being faced by younger people.

"The Democratic Party has to do something to get the energy among the younger voters," Reeves Canty said. After voting for Biden in 2020, she said she is leaning towards supporting him again.

(Reporting by Trevor Hunnicutt; Editing by Heather Timmons and Diane Craft)

By Trevor Hunnicutt