Being the Public Policy Researcher that I am, I got into a discussion with my boss one day about the Scripps Howard survey which found 36% of America believing in either LIHOP or MIHOP. The exact question was:

There are also accusations being made following the 9/11 terrorist attack. One of these is:
People in the federal government either assisted in the 9/11 attacks or took no action to stop the attacks because they wanted to United States to go to war in the Middle East.*

Very likely 16%
Somewhat likely 20%
Not likely 59%
Don't know 5%

*This question had 992 respondents; it was part of a survey posted on newsPolls.org on July 6, 2006.

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I went to the Scripps Howard News Service online, only to find dead links to all of their data files. I contacted the webmaster and then received the data file from Mr. Guido Stempel himself. It's in SPSS format, so the program to view it with is available here.

http://www.spss.com/

You can download the data file here:

http://www.box.net/shared/qf1qsq323n

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Update: LESS THAN A THIRD OF AMERICA BELIEVES

After subtracting the 17 respondents who left this question blank from the 1010 total, there are 993 respondents, not 992. The index is listed as follows: 1 is "Very Likely", 2 is "Somewhat Likely", 3 is "Unlikely" and 4 is "Don't Know", 5 is "Other Response" and 6 is "Not Ascertained." To nitpick, if "Other Response" was listed as an option for the test takers, it should've been included in the results, mho. 135 respondents chose ones, 179 twos, 616 threes, 53 fours, 10 fives, and 17 sixes.

Using 993 as 100%, I show 13.6% responding "Very Likely."
If "Other Response" gets ruled out, we get 983 as 100%, but still only 13.7%.
If "Don't Know" also gets ruled out, which would seem absurd, we still only get 14.5%.

After emailing Mr. Stempel for clarification, his only response was that he gave me unweighted data in contrast to the data used in the article, which was "weighted to match Census Bureau demographics on sex, race, income and
education." In conclusion, if everyone who took the survey were created equal, less than a third of America actually believes we attacked ourselves or intentionally allowed the attacks to occur.