Mr. Mehlman ran Bush's presidential campaign in 2004, and would have been a party to the agenda of hostility towards gay and lesbian rights during the campaign, which was designed to encourage religious and conservative supporters to vote, reported The Guardian.
"It's taken me 43 years to get comfortable with this part of my life," said Mehlman in an interview published on The Atlantic website.
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"Everybody has their own path to travel, their own journey, and for me, over the past few months, I've told my family, friends, former colleagues, and current colleagues, and they've been wonderful and supportive. The process has been something that's made me a happier and better person. It's something I wish I had done years ago."
While there had previously been speculation about his sexuality, Mr. Mehlman had always denied he was gay and he is the most senior Republican figure to ever have publically admitted homosexuality.
In the last few months, Mr. Mehlman has reportedly been working as a strategist and fund-raiser for the American Foundation for Equal Rights, which supports a legal challenge to Proposition 8, the California ballot measure that banned same-sex marriage, the New York Times reported.
