By Hillary Busis
Updated March 01, 2013 at 11:06 PM EST

Over 100 prominent Republicans have signed the American Foundation for Equal Rights’s “Friend of the Court” brief, which the gay rights organization filed with the Supreme Court this week — including Clint Eastwood, the 82-year-old actor, director, and California resident who made a memorable appearance at last year’s Republican National Convention.

Next month, the Court will hear arguments about the legality of California’s Proposition 8, a constitutional amendment passed in 2008 that declares “only marriage between a man and a woman is valid or recognized in California.” If Prop 8’s opponents are victorious, the state’s gay marriage ban could be overturned. President Obama has urged the Court to eliminate the ban; in a poll this week, a record 61 percent of California residents said that they support the right of same-sex couples to marry.

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