King played a notable role in the nomination of Jimmy Carter as the Democratic candidate for president in the 1976 election. After Carter's success in the Iowa caucus, the New Hampshire primary and the Florida primary, some liberal Democrats were worried about his success and began an "ABC" ("Anyone But Carter") movement to try to head off his nomination. King pointed to Carter's leadership in ending the era of segregation in Georgia and helping to repeal laws restricting voting which especially disenfranchised African Americans. With King's support, Carter continued to build a coalition of black and white voters and win the nomination. King delivered the invocation at the 1976 and 1980 Democratic National Conventions. King was also a member of Omega Psi Phi.