Mystery Pollster notes that in The War Room, a documentary that followed James Carville and George Stephanopoulos during Bill Clinton's 1992 campaign, "one of the final scenes shows Clinton's operatives reacting to the first leaked exit poll results."
By pausing the DVD, we can see the handwritten leaked numbers and "it is obvious that these mid-day reports in 1992 were off by nearly as much as the leaked numbers everyone saw on the Internet in the middle of the Election Day, 2004."
This doesn't prove exit polls are biased to favor Democrats, but it does show errors are more frequent than we previously thought. The key differences were that Clinton still won the election and "the Internet was in its infancy, so the leaked results spread to a few hundred reporters and politicos, not the millions that saw the leaked exit polls in 2004."
One other great tidbit: It appears Warren Mitofsky, the director of the 2004 exit polls, leaked the data to the Clinton campaign in 1992.
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