I've been reading David Westin's 2012 book Exit Interview. Westin was President of ABC News during the Bush-Gore election in 2000 and in his book, Westin recounts the difficulties of all the networks in determining who had won Florida and with that victory the Presidency. Exit polling suggested that Gore was the winner and, on that basis, the networks had awarded Gore the Presidency. When, after all the ballots had been counted and recounted, the Supreme Court decided that Bush had won the election. Exit polling was condemned as inaccurate. It has never regained the esteem in which it was once held.
So far as I know, I am the first to suggest that the exit polling in 2000 was entirely accurate. The key area was Palm Beach County where the voters were utilizing the infamous "butterfly ballots." Many voters who thought they were voting for Al Gore were, because of the butterfly ballot, voting for Pat Buchanan, a third party candidate. When they were asked as they exited the polls whom they had voted for, they said Al Gore. The pollsters reported those numbers to exit polling headquarters and headquarters wrote them into their overall number count and included them in the numbers they sent on to AP, the networks and other subscribers. The subscribers accepted the numbers and declared Gore President.
It took a few hours before actual numbers came in, indicating that Florida was up for grabs and the networks moved Gore from the winners list to undecided. The vote was so close that Florida was counting and recounting the numbers, waiting for the absentee ballots and a recount of the Palm Beach votes, that the Supreme Court finally took the case out of the hands of Florida and named George Bush the winner.
The networks were widely regarded as the villains of the piece. They had named the winner too soon and were no longer to be relied on. The networks blamed the exit polls on which they had relied. Exit polling got a bad name and no longer carry the clout they used to. Many Americans no longer thought they mattered and since then networks have been much more careful in declaring winner. In his book, Westin rests the blame for ABC's announcement largely on his shoulders. He doesn't go overboard about the problems with Florida's exit polls, but others do.
I stand alone in proclaiming that exit polls got it exactly right in the 2000 Presidential Race. They reported just what they heard from the Palm Beach County voters -- that the voters had been foxed by the ballot either intentionally or unintentionally never entered their minds. The foxers, if they did indeed use butterfly ballots to confuse voters, have never admitted it, but in this context that doesn't matter. I believe accuracy lost out to trickery and exit polls were unfairly blamed.