COLUMBIA, SC - JANUARY 18, 2016: Democratic presidential candidate, former Maryland Gov. Martin O'Malley listens to a service honoring Rev. Martin Luther King Jr. at Zion Baptist Church Monday, January 18, 2016 in Columbia, South Carolina. Following the service those in attendance marched to the S.C. State House for the annual King Day at the Dome rally, organized by the NAACP. (Photo by Sean Rayford/Getty Images)