Hubert Humphrey was Johnson's Vice President, and he run for the highest office in 1968, losing to Richard Nixon. His campaign was haunted by the anti-war protesters, Johnson's reluctance to halt the bombing of North Vietnam, and Robert Kennedy's bid for President.

Humphrey was branded a warmonger by the anti-war movement, who vehemently protested his nomination as the Democratic candidate in the Convention held in Chicago in 1968. Humphrey's draft platform for Vietnam was fairly moderate, in order to attract the former supporters of Robert Kennedy and the liberal democratic wing of Eugene McCarthy. Unfortunately for Humphrey's presidential hopes, Lyndon Johnson refused to endorse such a moderate plan, and Humphrey ended up losing the elections largely on the Vietnam issue.

Biography of Hubert H. Humphrey
From the Encyclopedia Americana http://gi.grolier.com/presidents/ea/vp/vphumph.html