(CBS News) More than 80 "conservative voices" have signed onto a legal brief supporting the notion that same-sex couples should have a fundamental right to marriage.
The brief is in support of the plaintiffs in the Hollingsworth v. Perry case now before the Supreme Court, which challenges California's Proposition 8 barring same-sex marriage. The case, which will be argued starting in late March, could result in the invalidation of statewide bans on same-sex marriage across the country. It is one of two same-sex marriage cases being considered this term by the Supreme Court; the other challenges the Defense of Marriage Act, which bars federal recognition of same-sex marriage.
Among the signatories to the letter are former Republican Governors Christie Todd Whitman and Bill Weld; Rep. Ileana Ros-Lehtinen, R-Fla.; former Republican Reps. Deborah Pryce and Mary Bono Mack; 2012 presidential candidates and former governors Gary Johnson and Jon Huntsman; and former Republican National Committee chair Ken Mehlman, the onetime George W. Bush campaign manager who has since come out as gay.
Notably not among the signatories are some Republicans who have expressed support for same-sex marriage in the past, including Dick Cheney and Laura Bush.
The American Foundation for Equal Rights, which organized the effort, said more names will be added before the brief is filed. The brief was first reported by the New York Times, which reported that it made the case that same-sex marriage reflects conservative values of "limited government and maximizing individual freedom."
Among those working to legalize same-sex marriage are conservative lawyer and former Solicitor General Theodore B. Olson, who was among the first prominent conservatives to express support for same-sex marriage. Same-sex marriage supporters hope the fact that numerous well-known conservatives and Republicans are signatories to the brief will help sway conservative justices.
"The conservative movement toward the freedom to marry is what we like to call the 'Ted Olson effect,'" said AFER executive director Adam Umhoefer. "We value the support of our conservative colleagues and welcome their voices to the growing majority of Americans who stand for marriage equality."
CBS News polling has found that a majority of Americans believe same-sex marriage should be legal, though more than six in ten said it should be left to the states to decide. House Speaker John Boehner and most Republicans in Congress oppose both federal recognition of same-sex marriage and a mandate that it be recognized by the states.
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