According to a 2013 Gallup poll, 61 percent of Americans believe John F. Kennedy’s assassination was the result of a conspiracy. Among those who don't think Lee Harvey Oswald acted alone, the same names keep popping up. Here are nine people and groups who've been blamed for killing the 35th President of the United States.

1. Lyndon B. Johnson

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A big contributor to this theory is Roger Stone, who wrote The Man Who Killed Kennedy: The Case Against LBJ. But Stone, a longtime Washington insider, is better known for having worked for Richard Nixon, Ronald Reagan, George H. W. Bush and, most recently (and controversially), Donald Trump.

Stone believes that Lyndon Johnson hired hitman Malcolm Wallace to do the dirty work, which explains an allegation that Johnson ducked before any shots were fired. Stone also believes that Johnson confessed to the crime: “Johnson’s mistress of 21 years, Madeleine Duncan Brown, who bore him an illegitimate son, said that Lyndon Johnson told her on the eve of the assassination, ‘After tomorrow I won’t have to deal with those Kennedy SOBs no more.’”

2. The KGB

Ion Mihai Pacepa, who was a general for the secret police of Communist Romania, blames the KGB for orchestrating the assassination in his book, Programmed to Kill: Lee Harvey Oswald, the Soviet KGB, and the Kennedy Assassination. As for how the Soviet security agency got connected with Lee Harvey Oswald, theorists cite Oswald’s residency in the Soviet Union from 1959 to 1962. During this time, Oswald also met and married his Russian wife, Marina. Before the Kennedy assassination, Oswald wrote a letter to his wife that contained the assertion, “I believe that the Embassy will come quickly.” Pacepa believes this note is a piece of evidence that the KGB told Oswald they would take care of his family.

In another theory, the KGB is responsible for the assassination, but Oswald is not. According to JFK assassination expert Bryan Ghent, these theorists suspect that Oswald “was replaced by a Russian agent who looked like him in order to assassinate our president.”

3. Fidel Castro

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Theories about Oswald’s connection to Cuba vary in extremity, and some of these theories claim Fidel Castro was directly involved in JFK’s death. As for evidence, Oswald was arrested in 1963 for passing out pro-Castro pamphlets for the New Orleans Fair Play for Cuba Committee. The other primary basis for this theory is Oswald’s trip to the Cuban Embassy, around two months before the assassination, where he allegedly had a meltdown because he wasn’t granted a visa.

In 1963, Castro—Cuba's longtime Prime Minister-turned-President, who passed away in 2016—was questioned about JFK’s assassination, but the U.S. government determined he was not involved.

4. Woody Harrelson's Dad

In 1980, Charles Harrelson was convicted of shooting federal judge John H. Wood, Jr. He was arrested in September of that year after a six-hour standoff with police on the side of a highway. During the saga, Harrelson confessed to the assassination of John F. Kennedy in addition to Judge Wood. He later stated he had nothing to do with the JFK assassination, claiming he only confessed to the crime to ensure that he would live longer.

5. Secret Service Agent George Hickey

In 1992, Bonar Menninger released his assassination theory in the book Mortal Error: The Shot That Killed JFK. The book details a claim that one of Kennedy’s Secret Service agents, who was riding in the car behind the president, shot Kennedy by accident. Menninger worked with Baltimore ballistics expert Howard Donahue to compile the evidence.

“It is a ballistically unshakable fact that the fatal shot came from a position behind and to the left of the president," Donahue told The Sunday Sun Magazine in 1977. The two theorists concluded that the shooter was agent George Hickey, who reacted to Lee Harvey Oswald’s first shot by shooting his own gun and further injuring JFK.

Hickey did acknowledge the accusation. He sued Menninger after the book was released, but St. Martin’s Press, the publisher of the book, settled.

6. The Central Intelligence Agency

According to author Patrick Nolan, who wrote CIA Rogues and the Killing of the Kennedys, a group of rogue CIA agents killed JFK. Nolan names James Angleton, Richard Helms, E. Howard Hunt, and David Phillips as members of the responsible group. He cites disagreement with Kennedy’s approach to Cuba as the group’s motive.

As for evidence, the most compelling is E. Howard Hunt’s deathbed confession to his family. Hunt, who was also involved in the Watergate Hotel break-in, allegedly revealed that the group of CIA rogues invited him to have a role in the assassination, which was originally supposed to take place in Miami before it was moved to Dallas. His son, Howard St. John Hunt, relayed his father's message to the Los Angeles Times, “He told me in no uncertain terms about a plot originating in Miami, to take place in Miami.”

7. Carlos Marcello

Lamar Waldron has written multiple books accusing the mafia of killing JFK. He also believes the CIA had a role in covering up the assassination. In his theory, mafia boss Carlos Marcello hired hitmen to assassinate Kennedy because the president and his brother, Attorney General Robert F. Kennedy, were too tough on mob-related crimes. In 1985, Marcello allegedly admitted to the murder, reportedly telling a fellow prisoner, “Yeah, I had the son of a bitch killed. I’m glad I did. I’m sorry I couldn’t have done it myself.”

8. Joe DiMaggio

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Even baseball legend Joe DiMaggio has been blamed for JFK's assassination. According to this theory, DiMaggio was sure that a member of the Kennedy family had had Marilyn Monroe killed. DiMaggio’s lawyer Morris Engelberg wrote that the Hall of Famer refused to go to events if there would be members of the Kennedy family there. DiMaggio apparently told Engelberg, “It’s in their blood, and what they did to me will never be forgotten. They murdered the one person I loved.” Even as crazy conspiracy theories go, this one's a little flimsy.

9. Alien Researchers

William Lester’s book, A Celebration of Freedom: JFK and the New Frontier, contains a letter from Kennedy to the CIA dated 10 days before the assassination. In the letter, Kennedy requested a “classification review of all UFO intelligence files affecting National Security.” Conspiracy theorists see a connection between this letter and Kennedy’s murder, blaming either a CIA cover-up or another alien research organization.

Lester maintains that the CIA gave him the letter, but government insiders believe the letter is a fake.

This article originally ran in 2013.