Mobster Sam Giancana.
Judith Campbell was her name.
Thanks! Those "Camelot Kennedy's" were really something, weren't they?! /sarcasm
Judith Campbell
In 1952 she married the actor William Campbell. After her divorce in 1958 she began a relationship with Frank Sinatra. During this period she also became involved with Mafia leader, Sam Giancana.
On 7th February, 1960 Frank Sinatra introduced Judith Campbell to John F. Kennedy at Palm Springs. During the 1960 presidential election Campbell took messages from Giancana to Kennedy. Campbell later claimed these messages concerned the plans to murder Fidel Castro. Kennedy also began an affair with Campbell and used her as a courier to carry sealed envelopes to Giancana. He told her they contained "intelligence material" concerning the plot to kill Castro.
In April 1975 she married a professional golfer called Dan Exner and settled in Orange County. Later that year Frank Church and his Select Committee on Intelligence Activities discovered that Judith Campbell had been involved with both John F. Kennedy and Sam Giancana. Church did not make this news public. She published her account of her relationship with these two men in the book, Judith Exner: My Story (1977).
Juditn Campbell Exner, to be exact!