People don’t support you because they like you. You can count on a person’s support only when you do something for him or something to him.
Lyndon B. Johnson (1908–1973) American politician, educator, US President (1963–69)
(Attributed)
(Source)
On support from Congress. An "embittered" comment made to Richard Nixon after Johnson had left the Presidency. Quoted in Richard Nixon, In the Arena: A Memoir of Victory, Defeat, and Renewal, ch. 21 (1990).

