Source: Anti-Defamation League
http://www.adl.org/PresRele/ASUS_12/4454_12.htm
On February 23, 2004 the Anti-Defamation League reported, "On the eve of the release of Mel Gibson's controversial film "The Passion of the Christ," a poll commissioned by the Anti-Defamation League (ADL) has found that one in four Americans believe that Jews were responsible for the death of Jesus.
A national poll of 1,200 American adults conducted December 1-4, 2003 by The Marttila Communications Group of Boston found that 25 percent of those surveyed accepted the statement, 'Do you think that Jews were responsible for the death of Christ?' as being 'probably true.' The poll has a margin of error of +/- 2.8 percent...
Despite decades of positive interfaith relations and teachings aimed at rejecting the notion of Jewish guilt in the Crucifixion, surveys over the last four decades have found that the question about 'deicide' has remained constant – at about 25 percent of the population. Previous ADL surveys on anti-Semitism in America have found that while the overall level of anti-Semitism has steadily declined since 1964, reaching historic lows in the late 1990s, the number of Americans who accept the canard that 'the Jews killed Christ' has remained virtually unchanged over a span of four decades."