The story
Sarcastic nickname from the fact that Lyndon B. Johnson's 1948 run to a be a Texas senator needed a runoff in order to be successful, which LBJ won by 87 votes over Coke Stevenson, in a state with a large population. After 1964, there were more sincere uses due to his 1964 United States presidential election landslide win over Barry Goldwater.
Etymology from Wiktionary, CC BY-SA 4.0.