This year, on the day our nation celebrates Dr. Martin Luther King Jr., I proudly stood alongside NAACP State Conference presidents on the steps of the capitol building in Columbia, S.C. for the annual King Day at the Dome March and Rally. The event has grown into a massive commemoration over the years, but this year it took on a new significance as Attorney General Eric Holder joined the commemoration, honoring Dr. King and pledging to carry forward his mission in the years ahead.

Looking out over the crowd of thousands, I reflected on how Dr. King risked everything to advance civil and human rights in America. How, despite repeated threats against his life, he spread the message of non-violent civil disobedience against unjust laws throughout the Jim Crow South and our nation as a whole.??

Dr. King’s leadership has inspired Americans to win big victories that have moved our nation closer to the long-expressed, but yet-unrealized ideal that our school children repeat every day: we are “one nation, under God, indivisible, with liberty and justice for all.” Yet today, one of the greatest victories Dr. King helped win during his lifetime is under withering attack: The Voting Rights Act and the rights it protects — for all Americans to be able to participate in free and fair elections. South Carolina has become ground zero in this battle.

On one side, civil rights activists and the U.S. Department of Justice are fighting on behalf of thousands upon thousands of voters who would be disenfranchised by laws that introduce the first new financial and literacy-based obstacles to voting since we eliminated the poll tax and voting tests. Fighting on behalf of Americans like the students at South Carolina’s Benedict College, whose student identification cards have been deemed insufficient for use as voter ID. And we are fighting on behalf of senior citizens born in South Carolina in a time when Blacks often were not issued birth certificates. Now, for the first time in their lives, they will need to pay upwards of $150 to obtain the documents required by South Carolina’s voter suppression law.

On the other side, governors like South Carolina’s Nikki Haley are suing to gut the Voting Rights Act after the Justice Department blocked the state’s discriminatory voter ID law.

It was an honor to stand alongside Attorney General Holder as we recommitted ourselves to protecting our most sacred of rights. NAACP State Conference presidents and our allies throughout the nation are leading the battles to defend voting rights this year, and that’s why it was so important that they led this march in South Carolina.

We marched to defend our right to vote and to defend our nation’s dream of America as a place where everybody works, everybody contributes, and everybody counts. We marched for good jobs that can support our families, and an education for our children that will pave the way for them to do the same. We marched to declare our intent to defeat the deeds of any governor who would deify our great dreamer, but desecrate his dream.

Dr. King’s dream will become a reality. It will take vigilance. It will take patience. It will take hard work. But together, we will win this fight and uphold the right to vote for all Americans in 2012 and beyond.

Benjamin Jealous is president and CEO of the NAACP.