As Barack Obama pulls ahead in the polls, pollsters are now debating the ‘Bradley effect’ – a theory that black candidates’ leads in polls won’t translate into votes.

The Washington Post reports: “Most experts say they do not believe that the phenomenon, known as the “Bradley effect,” is at work in this election. But some disagree. And if the effect has disappeared, it is not clear whether that is because polling techniques have improved or because the country has become more tolerant about race.

“The phenomenon got its name a generation ago, after former Los Angeles mayor Tom Bradley (D), an African American, lost the 1982 gubernatorial race in California despite leading his white opponent in the polls on the eve of the election. Some experts suspected at the time that a portion of white voters, reluctant to appear biased, had essentially lied to pollsters about which candidate they were supporting. But whether Bradley lost because of hidden racism has never been clear.”

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