Theodore H. White
Clark first met Senator Eugene McCarthy in 1965 at a party at Walter Lippmann's house in Washington, D.C. Two years later, when McCarthy announced that he would challenge President Lyndon Johnson in the 1968 Democratic primaries as an anti-war candidate, Clark wrote to McCarthy from London to express his support. With his friend Theodore H. White, Clark traveled to Chicago in December 1967 to hear McCarthy address the Conference of Concerned Democrats, a group of antiwar activists. Soon after meeting in Chicago, McCarthy asked Clark to be his campaign manager.