There have been persistent rumors over the years of links between JFK and the Mafia. A purported presidential mistress, Judith Campbell Exner, once claimed she had arranged a meeting at JFK's behest with Chicago crime boss Sam Gianciana, so that JFK could seek Gianciana's help during the 1960 presidential race [source: Associated Press]. It's also well-documented that the CIA sought mobsters' help in its plots to assassinate Cuban dictator Fidel Castro [source: Kessler].
But the Mafia eventually came to view JFK and his brother, Attorney General Robert F. Kennedy, as bitter adversaries because of the latter's efforts to eradicate mob influence over the Teamsters union [source: Krauss]. Frank Ragano, an attorney who represented Teamsters president Jimmy Hoffa, wrote a 1994 book in which he alleged that Hoffa asked mob bosses Santos Trafficante and Carlos Marcello to arrange JFK's assassination. (Of course, Hoffa mysteriously disappeared in 1975 and was declared legally dead in 1982.) Ragano also claimed that, in 1987, a dying Trafficante confessed to having a role in the president's killing and expressed his regrets, saying, "We should have killed Bobby" instead [source: Noble].
The mob hit is probably the conspiracy theory that comes the closest to being plausible — even House Select Committee on Assassinations (HSCA) counsel G. Robert Blakey said in 1979,"I think the mob did it" [source: Bugliosi].But with the possible suspects and their associates long dead, the chances of turning up solid proof seem increasingly remote.