New Hampshire's primary grabs headlines today, but if history is any guide, the Jan. 21 South Carolina primary will play a far greater role in determining the Republican winner.

Of that state's population, 28 percent are African American, and could be a major factor in the primary. But Republican candidates have made little effort to reach out to the black community. Republican South Carolina voters are likely to be nearly as white as they were in Iowa and New Hampshire. All the Republican candidates will pay tribute to Dr. King on his birthday next week, but they seem oblivious to one of his greatest contributions: the creation of the New South.

In a time of growing inequality, we forget the scope of Dr. King's victory. When I was growing up in Greenville, S.C., segregation was the law of the land. Blacks and whites attended separate and unequal schools. My friends and I were locked out of public institutions like the public library. We still rode in the back of the bus. Greenville was the home of Bob Jones University, which Africans could attend (if they didn't fraternize with white women) while African Americans could not. If we wanted to play college sports, we either attended a historically black institution or went to schools in the North or West.

South Carolina's political leadership fiercely resisted the movement for civil rights. My first arrest came from trying to use the public library. It took years of struggle, demonstrations, sit-ins, bloodshed and sacrifice, but in the end, Dr. King had a more powerful vision of the future than all of the politicians, sheriffs and elites who stood in the way.

The victory of the civil rights movement helped to forge a new South. In South Carolina, public schools and public accommodations are open to all. Colleges are integrated. Students from Clemson or South Carolina root for their teams, loyalties divided by the color of the uniform, not the color of the players. With the ending of legal segregation, the economy started to modernize. Foreign investors opened plants that would not have come to the Old South. African Americans gained the right to vote.

Now the Republican governor of South Carolina, Nikki Haley, is of South Asian descent. The New South has come a long way, but has a long way yet to go. In South Carolina, the Republican Party consolidated its power through a poisonous race-bait politics, as it did throughout the South. The inequality rooted in 150 years of slavery and 100 years of legal apartheid has not been overcome. African Americans in the New South have less wealth, more poverty and worse unemployment than whites. In South Carolina, 37 percent of African Americans live in poverty, compared with 15 percent of whites.

Dr. King understood that the civil rights movement, having ended segregation and gained the right to vote, had to challenge poverty and economic inequality. In his final days, he was building a poor people's campaign, planning to bring people to the nation's capital across lines of race, religion and region to create a Resurrection City and demand economic justice. He was the true precursor of Occupy Wall Street.

It is fitting that we celebrate Dr. King's birthday the week before the first Southern primary. Republicans still tout Reagan's vision, but it was King, not Reagan or Thurmond who forged the New South. And it is King's unfinished agenda -- how to guarantee equal opportunity and economic justice for all -- that they must address.

Over time, Republicans may just find that a party of white sanctuary and trickle-down economics has less and less appeal in a South where race concerns people less and economic opportunity worries them more.

Follow Rev. Jesse Jackson on Twitter: www.twitter.com/revjjackson