Frank Sinatra was a Reagan supporter, I might add.
BS! Back then Republicans were leading the charge in the Civil Rights movement...Jackie Robinson was a Republican then.
Prior to Sinatra’s support for Reagan, he and the other members of the Rat Pack supported John Kennedy in his bid for the WH. But there was a falling out and Sinatra later became a Republican.
The rat pack were liberals as was almost everyone in show business at that time. Even Reagan was a liberal Democrat during his acting career. Sinatra and the rat pack greatly helped Sammy Davis Jr.’s career and created opportunities for him.
Politically Sinatra was an opportunist. Peter Lawford was Kennedy's brother-in-law, the rat pack called him Pater brother in Lawford. Sinatra helped procure women for Kennedy(and Giancana), got acting jobs for Peter Lawford, entertained Kennedy and tried very hard to gain Kennedy's favor.
J. Edgar Hoover discovered the relationships between Giancana, Sinatra and Judy Campbell a Kennedy mistress who often visited the White House for sex. Hoover told Bobby Kennedy and Bobby canceled Kennedy's visit to Sinatra's “western White House”.
This caused Sinatra's break with the Kennedy's and ended Peter Lawford’s acting career.
A few years later Sinatra and the other rat pack members became conservative Republicans and supporters of Nixon and Ronald Reagan. Sammy Davis Jr. praised Nixon and hugged in front of photographers.