A CLEAR majority of Americans still suspect there was a conspiracy behind President John F. Kennedy's assassination, according to a new poll.
But the percentage who believe accused shooter Lee Harvey Oswald acted alone is at its highest since the mid-1960s.
According to the AP-GfK survey, conducted in mid-April, 59 per cent of Americans think multiple people were involved in a conspiracy to kill the president, while 24 per cent think Oswald acted alone, and 16 per cent are unsure.
A 2003 Gallup poll found 75 per cent of Americans felt there was a conspiracy.
As the 50th anniversary of Kennedy's death approaches, the number of Americans who believe Oswald acted alone is at its highest since the period three years after the November 22, 1963 assassination, when 36 per cent said one man was responsible.
Among those who believe Oswald acted alone is Pat Sicinski, a retired school employee in Houston who along with her husband, recently visited the Texas School Book Depository in Dallas.
Looking out the sixth-floor window from which Oswald allegedly fired on Kennedy's motorcade helped reaffirm her faith in the Warren Commission's conclusion Oswald was the lone gunman.
President Lyndon B. Johnson appointed the Warren Commission on November 29, 1963 to investigate both Kennedy's assassination and the killing of Oswald days later.
"Some skepticism is always justified," says Sicinski, 68.
"I just think when people take it to extremes, they lose me."
On the other hand, Cheryl Casati says she's "extremely sure" there was a conspiracy.
The killing of Oswald just days after the assassination is part of the reason why.
"There's too many holes in explanations," says the 62, who retired from the Air Force after 20 years.
"That just could not have happened easily in that time and place. And (Jack) Ruby shooting (Oswald) could not have happened as easily as it did."
Those who were adults in 1963 were almost as likely as younger Americans to say Kennedy's killing was a conspiracy involving multiple people - 55 per cent, compared to 61 per cent.
The Associated Press-GfK Poll was conducted April 11-15, 2013 by GfK Roper Public Affairs and Corporate Communications.
It involved landline and cellphone interviews with 1004 adults nationwide.