A Brief History Of: Exit Polls

On Nov. 4, in a room somewhere in New York City, cut off from the outside world, a small group of media representatives will spend hours poring over polling data from around the country. No cell phones or Internet connections will be allowed, and the group will not emerge until 5 p.m. E.T. These people are part of the National Election Pool (NEP)--and they owe their monastic retreat to a long-running debate on how early election reports can affect the outcome of a race.

Networks began exit polling--surveying people leaving voting locations about the ballots they cast--in the 1960s, and it soon became a common tool to predict winners before votes were tallied. But after NBC reported Ronald Reagan's 1980 victory over Jimmy Carter hours before polls closed on the West Coast, Congress held hearings on whether the practice depressed voter turnout, and networks vowed not to project a state's winners until polls close. (Exit polling is protected by the First Amendment.)

In the 1990s, the major news networks and the Associated Press formed a polling consortium to cut costs, but this proved disastrous in 2000, when it declared the race for Al Gore around 8 p.m., switched to George W. Bush by 2 a.m. and left the race at "too close to call" by 4 a.m. An embarrassing computer glitch in 2002 prompted a switch to the NEP, which surveys early voters by phone, uses confidential questionnaires in the field and employs a diverse group of pollsters to ensure an accurate count. A leak of NEP data in 2004, however, prompted the creation of the current quarantine system, in use since '06.

Quarantine or no, news outlets still remember Florida in 2000; if swing-state races appear tight when the last polls close, odds are the media will be cagier about releasing early results--no matter how good the data look.