W. Mark Felt was Deep Throat, claims Vanity Fair. In 2003, students at the University of Illinois presented a convincing case that Fred Fielding was Woodward and Bernstein's key source when they broke the Watergate story in the Washington Post. But Felt, formerly the #2 spook in the FBI, says he really was the guy.
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UPDATE: The identity of Deep Throat has been confirmed as W. Mark Felt. From CNN:
"W. Mark Felt was 'Deep Throat' and helped us immeasurably in our Watergate coverage," according to a statement issued by Woodward and Bernstein.
"However, as the record shows, many other sources and officials assisted us and other reporters for the hundreds of stories that were written in The Washington Post about Watergate."
