It was to unite blacks and whites to campaign for fundamental changes in American society and economic structure .
Rev. Ralph Abernathy succeeded King as the head of the SCLC and attempted to carry forth King 's plan for a Poor People 's March .
SCLC was to unite blacks and whites to campaign for fundamental changes in American society and economic structure .
Rev. Ralph Abernathy succeeded King as the head of the SCLC and attempted to carry forth King 's plan for a Poor People 's March .