On March 31, 1968, President Lyndon Johnson stunned the nation when he announced he would not run for re-election. The 1968 presidential campaign and election were watershed moments in U.S. history. Learn more about the candidates and how Richard Nixon and Hubert Humphrey gained their party's nomination. Find out the answers to these questions: How did Nixon come back from the political graveyard? Why did LBJ undermine his fellow Democrat Hubert Humphrey? Did Nixon commit treason during the campaign? What impact did George Wallace have on the election? Could Humphrey have won the presidency?