McCarthy's decision to run arose partly as an outcome of Oregon Senator Wayne Morse's opposition to the war. Morse was one of two senators to vote against the Gulf of Tonkin Resolution of August 1964. He gave speeches denouncing the war before it had entered most Americans' awareness. Thereafter, several politically active Oregon Democrats asked Kennedy to run as an antiwar candidate. McCarthy also encouraged Kennedy to run. After Kennedy refused, the group asked McCarthy to run, and he responded favorably. After Kennedy entered the race and Johnson withdrew, however, McCarthy shifted his focus toward Kennedy.