Ask any American who they think killed President John F. Kennedy, and you’re sure to receive a wide range of answers.
There’s the official government conclusion from the Warren Commission that Lee Harvey Oswald acted alone when he killed the president on November 22, 1963 in Dallas.
And then there’s the wide swath of conspiracy theories that Oswald had help from other people, a belief that a majority of Americans have always held, according to Gallup.
Right after Kennedy’s death, Gallup found that 52 percent of Americans thought Oswald was part of a larger conspiracy, with just 29 percent saying he did it all by himself. The belief that others worked alongside Oswald has never dipped below 50 percent in Gallup polling, and peaked at 81 percent in 1976.
Gallup is not alone in its findings. FiveThirtyEight commissioned a SurveyMonkey poll this month to ask the same question.
Overall, FiveThirtyEight had the same findings as Gallup did in its latest poll in 2013: 61 percent of Americans believe Kennedy “wasn’t killed by Oswald alone.” Only 33 percent say it was just Oswald.
Of all the demographic groups polled, only one had a minority of conspiracy believers — white college graduates, with 46 percent holding that belief.
Here are a few of the popular theories that fuel the disconnect between the official government findings and public opinion.
A Second Shooter
Separate from the Warren Commission, President Lyndon B. Johnson tasked the House of Representatives Select Committee on Assassinations with official fact-finding on who killed JFK. The House report found a "high probability" that two gunmen fired at Kennedy.
This led to the popularization of the term "grassy knoll," alluding to a hill near Dealey Plaza from where some believe Kennedy's true killer fired.
The Oliver Stone Film "JFK" posits the idea that the CIA or people associated with the CIA were involved in some way in the Kennedy assassination. Theories range from mild complicity on the CIA's part to suggestions that a CIA operative actually fired the deadly shot.
Seven percent of Americans who think Oswald had help say the CIA was involved, according to Gallup’s 2013 survey.
The House Select Committee report said the CIA "was deficient in its collection and sharing of information both prior to and subsequent to the assassination."
Fidel Castro and Cuba
Earlier in his presidency, Kennedy had signed off on an operation known as the Bay of Pigs Invasion, which ended with a failed attempt to overthrow Fidel Castro's communist government.
Following that botched attempt and the Cuban Missile Crisis, one theory goes that Castro had a hand in the assassination, perhaps through some loose association with Lee Harvey Oswald.
Many have speculated that the documents scheduled to be released on Oct. 26 would contain information on Oswald's visit to Mexico two months before the Kennedy assassination, where he may have met with either Cuban or Soviet officials.
This is a belief that 5 percent of Americans who believe in the conspiracy hold, Gallup found.
Most of these theories center around the Cold War tensions of the time in 1963, but many believe it was as simple as a mafia hit.
Kennedy’s brother Robert was attorney general at the time of his big brother’s assassination, and had made it a point to go after organized crime. The House Select Committee’s report concluded that the mafia was not involved, but it did not rule out specific members of the mafia.
In 2013, Gallup found that 13 percent of Americans who believe Kennedy was killed in a conspiracy plot blame the Mafia.