A long list of well-known Republicans have signed on to a legal brief being filed with the U.S. Supreme Court encouraging the justices to overturn California’s controversial Proposition 8, which constitutionally prohibited gay marriage in the state after it was approved by the voters in 2008.

At least 80 Republicans so far have attached their names to the amicus brief, a legal document that is used for third party groups to inject their opinion into cases for the Supreme Court to consider in their deliberations. The Court will hear arguments for and against Proposition 8 next month.

Californians will see a couple familiar names on the list. Meg Whitman, the Republican Party’s 2010 gubernatorial candidate in California, has signed onto the brief. Whitman supported Proposition 8 and promised to oppose efforts to repeal it during that campaign. She says her opinion has since changed. “Marriage is the fundamental institution that unites a society. It is the single greatest contributor to the well-being of adults and children because it promotes eternal principles like commitment, fidelity and stability,” Whitman wrote in a statement. “It makes no difference whether the marriage is between a man and woman or a woman and woman. Marriage makes society better.”

Former GOP Congresswoman Mary Bono Mack, who lost her Palm Springs seat last year, is also on the list, as is Aaron McClean, who served as press secretary to former Gov. Arnold Schwarzenegger during his second term.

Clint Eastwood, the famed Hollywood star who caused an exciting (and, for some, frustrating) stir among Republican circles for his “empty chair” speech at last summer’s Republican National Convention, is also a signer.

The amicus brief argues that there is “no basis” for a discriminatory law like Proposition 8, and that gay marriage is actually a benefit to children who otherwise would have no parents. A well-placed Republican source with knowledge of the amicus brief, on condition of anonymity, provided the following excerpt to California Briefing:

“Whether same-sex couples should have access to civil marriage divides thoughtful, concerned citizens.  But this Court has long recognized that a belief, no matter how strongly or sincerely held, cannot justify a legal distinction that is unsupported by a factual basis, especially where something as important as civil marriage is concerned. …  Our constitutional tradition requires the judiciary to protect our most cherished liberties against overreaching by the legislature or the electorate, and that principle, no less than our commitment to democratic self-government, is necessary to individual freedom and limited government.  It is precisely at moments like this-when discriminatory laws appear to reflect unexamined, unfounded, or unwarranted assumptions rather than facts and evidence, and the rights of one group of citizens hangs in the balance-that this Court’s intervention is most needed.”

The list also includes former Bush Administration officials, governors, members of Congress, Republican National Committee staffers, and Romney campaign staffers. The move is a remarkable turn of events for a Party that is still largely opposed to gay marriage – House Republicans are leading the charge in court to defend the Defense of Marriage Act, which allows states to pursue their own laws on the issue, and which the Obama Administration would like to see overturned. But the amicus brief may be a “tip of the iceberg” sign of growing ranks of Republicans who are reversing their previous positions and coming out in support of gay marriage.

However, as detractors point out, the majority of the signers are now out of office, suggesting it may be easier to support gay marriage once Republicans no longer have to face their Party and the base.

See below for the full list of Republicans signing on to the amicus brief:

• Clint Eastwood, Producer, Director, Actor, Mayor
• Paul Wolfowitz, President of the World Bank Group (2005-2007) and Deputy Secretary of Defense (2001-2005)
• Cliff S. Asness, Businessman, Philanthropist, and Author
• Charlie Bass, Member of Congress, 1995-2007 and 2011-2013
• Thomas J. Christensen, Deputy Assistant Secretary of State for East Asian and Pacific Affairs, 2006-2008
• Jeffrey Cook-McCormac, Senior Advisor, American Unity PAC
• S.E. Cupp, Author and Political Commentator
• Michele Davis, Assistant Secretary for Public Affairs and Director of Policy Planning, Department of the Treasury, 2006-2009
• Janet Duprey, New York State Assemblywoman, 2007-Present
• Tyler Deaton, Secretary, New Hampshire Young Republicans, 2011-Present
• Chris Edwards, Special Assistant to the President and Director of Press Advance, 2005-2007
• Mark J. Ellis, State Chairman, Maine Republican Party, 2005-2006 and 2007-2009
• Juleanna Glover, Press Secretary to the Vice President, 2001-2002
• John Goodwin, Chief of Staff to Raul Labrador, Member of Congress,2011-2013
• Mark Grisanti,  New York State Senator, 2011-Present
• Douglas Holtz-Eakin, Director, Congressional Budget Office, 2003-2005
• Cyrus Krohn, Digital Director, Republican National Committee, 2007-2009
• Kathryn Lehman, Chief of Staff, House Republican Conference, 2003-2005
• Alex Lundry, Director of Data Science, Romney for President, 2012
• Beth Myers, Romney for President Campaign Manager, 2007-2008 and Senior Advisor, 2011-2012
• B.J. Nikkel, Colorado State Representative and Majority Whip, 2009-2012 and District Director for Congresswoman Marylyn Musgrave, 2002-2006
• Richard Painter, Associate Counsel to the President, 2005-2007
• Ruth Ann Petroff, Wyoming State Representative, 2011-Present
• Gregg Pitts, Director, White House Travel Office, 2006-2009
• J. Stanley Pottinger, Assistant U.S. Attorney General (Civil Rights Division), 1973-1977
• John Reagan, New Hampshire State Senator, 2012-Present
• Adam Schroadter, New Hampshire State Representative, 2010-Present
• Richard Tisei, Massachusetts State Senator and Senate Minority Leader, 1991-2011
• John Ullyot, Communications Director, U.S. Senate Armed Services Committee, 2003-2007
• Sally A. Vastola, Executive Director, National Republican Congressional Committee, 2003-2006
• Jacob P. Wagner, Chairman, New Hampshire Federation of College
• Republicans, 2012-Present
• Dan Zwonitzer, Wyoming State Representative, 2005-present
• Frances Fragos Townsend, Homeland Security Advisor to the President, 2004-2008
• Brian Roehrkasse, Director of Public Affairs, Department of Justice, 2007-2009
• Larry Pressler, U.S. Senator from South Dakota, 1979-1997
• Neel Kashkari, Interim Assistant Secretary of the Treasury for Financial Stability, 2008-2009
• Aaron Mclean, Press Secretary to Governor Arnold Schwarzenegger, 2007-2011
• Luis Reyes, Special Assistant to the President, 2006-2008 [or Deputy Associate Attorney General, U.S. Department of Justice, 2005-2006]
• Josh Ginsberg, Deputy Political Director, Arnold Schwarzenegger for Governor, 2006
• Meghan O’Sullivan, Deputy National Security Advisor for Iraq and Afghanistan, 2004-2007
• Jill Hazelbaker, Communications Director, John McCain for President, 2007-2008
• Corry Schiermeyer, Director Global Communications, National Security Council, 2005-2007
• Alicia Davis Downs, Associate Political Director, White House, 2001-2003
• Ken Mehlman, Chairman, Republican National Committee, 2005-2007
• Tim Adams, Undersecretary of the Treasury for International Affairs, 2005-2007
• David D. Aufhauser, General Counsel, Department of Treasury, 2001-2003
• Cliff S. Asness, Businessman, Philanthropist, and Author
• John B. Bellinger III, Legal Adviser to the Department of State, 2005-2009
• Katie Biber, General Counsel, Romney for President, 2007-2008 and 2011-2012
• Mary Bono Mack, Member of Congress, 1998-2013
• William A. Burck, Deputy Staff Secretary, Special Counsel and Deputy Counsel to the President, 2005-2009
• Alex Castellanos, Republican Media Advisor
• Paul Cellucci, Governor of Massachusetts, 1997-2001, and Ambassador to Canada, 2001-2005
• Mary Cheney, Director of Vice Presidential Operations, Bush-Cheney 2004
• Jim Cicconi, Assistant to the President & Deputy to the Chief of Staff, 1989-1990
• James B. Comey, United States Deputy Attorney General, 2003-2005
• R. Clarke Cooper, U.S. Alternative Representative, United Nations Security Council, 2007-2009
• Julie Cram, Deputy Assistant to the President and Director White House Office of Public Liaison, 2007-2009
• Michele Davis, Assistant Secretary for Public Affairs and Director of Policy Planning, Department of the Treasury, 2006-2009
• Kenneth M. Duberstein, White House Chief of Staff and Assistant to the President, 1981-1984 and 1987-1989
• Lew Eisenberg, Finance Chairman, Republican National Committee, 2002-2004
• Elizabeth Noyer Feld, Public Affairs Specialist, White House Office of Management and Budget, 1984-1987
• David Frum, Special Assistant to the President, 2001-2002
• Richard Galen, Communications Director, Speaker’s Political Office, 1996-1997
• Mark Gerson, Chairman, Gerson Lehrman Group and Author of The Neoconservative Vision: From the Cold War to the Culture Wars and In the Classroom: Dispatches from an Inner-City School that Works
• Benjamin Ginsberg, General Counsel, Bush-Cheney 2000 & 2004
• Adrian Gray, Director of Strategy, Republican National Committee, 2005-2007
• Richard Grenell, Spokesman, U.S. Ambassadors to the United Nations, 2001-2008
• Patrick Guerriero, Mayor, Melrose Massachusetts and member of Massachusetts House of Representatives, 1993-2001
• Carlos Gutierrez, Secretary of Commerce, 2005-2009
• Stephen Hadley, Assistant to the President and National Security Advisor, 2005-2009
• Richard Hanna, Member of Congress, 2011-Present
• Israel Hernandez, Assistant Secretary of Commerce for International Trade, 2005-2009
• Margaret Hoover, Advisor to the Deputy Secretary of Homeland Security, 2005-2006
• Michael Huffington, Member of Congress, 1993-1995
• Jon Huntsman, Governor of Utah, 2005-2009
• David A. Javdan, General Counsel, United States Small Business Administration, 2002-2006
• Reuben Jeffery, Undersecretary of State for Economic, Energy, and Agricultural Affairs, 2007-2009
• Greg Jenkins, Deputy Assistant to the President and Director of Presidential Advance, 2003-2004
• Coddy Johnson, National Field Director, Bush-Cheney 2004
• Gary Johnson, Governor of New Mexico, 1995-2003
• Robert Kabel, Special Assistant to the President for Legislative Affairs, 1982-1985
• Theodore W. Kassinger, Deputy Secretary of Commerce, 2004-2005
• Jonathan Kislak, Deputy Undersecretary of Agriculture for Small Community and Rural Development, 1989-1991
• David Kochel, Senior Advisor to Mitt Romney’s Iowa Campaign, 2007-2008 and 2011-2012
• James Kolbe, Member of Congress, 1985-2007
• Jeffrey Kupfer, Acting Deputy Secretary of Energy, 2008-2009
• Kathryn Lehman, Chief of Staff, House Republican Conference, 2003-2005
• Daniel Loeb, Businessman and Philanthropist
• Alex Lundry, Director of Data Science, Romney for President, 2012
• Greg Mankiw, Chairman, Council of Economic Advisers, 2003-2005
• Catherine Martin, Deputy Assistant to the President and Deputy Communications Director for Policy & Planning, 2005-2007
• Kevin Martin, Chairman, Federal Communications Commission, 2005-2009
• David McCormick, Undersecretary of the Treasury for International Affairs, 2007-2009
• Mark McKinnon, Republican Media Advisor
• Bruce P. Mehlman, Assistant Secretary of Commerce, 2001-2003
• Connie Morella, Member of Congress, 1987-2003 and U.S. Ambassador to the Organization for Economic Co-operation and Development, 2003-2007
• Michael E. Murphy, Republican Political Consultant
• Michael Napolitano, White House Office of Political Affairs, 2001-2003
• Ana Navarro, National Hispanic Co-Chair for Senator John McCain’s Presidential Campaign, 2008
• Noam Neusner, Special Assistant to the President for Economic Speechwriting, 2002-2005
• Nancy Pfotenhauer, Economist, Presidential Transition Team, 1988 and President’s Council on Competitiveness, 1990
• J. Stanley Pottinger, Assistant U.S. Attorney General (Civil Rights Division), 1973-1977
• Michael Powell, Chairman, Federal Communications Commission, 2001-2005
• Deborah Pryce, Member of Congress, 1993-2009
• Kelley Robertson, Chief of Staff, Republican National Committee, 2005-2007
• Ileana Ros-Lehtinen, Member of Congress, 1989-Present
• Harvey S. Rosen, Member and Chairman, Council of Economic Advisers, 2003-2005
• Lee Rudofsky, Deputy General Counsel, Romney for President, 2012
• Patrick Ruffini, eCampaign Director, Republican National Committee, 2005-2007
• Steve Schmidt, Deputy Assistant to the President and Counselor to the Vice President, 2004-2006
• Ken Spain, Communications Director, National Republican Congressional Committee, 2009-2010
• Robert Steel, Undersecretary of the Treasury for Domestic Finance, 2006-2008
• David Stockman, Director, Office of Management and Budget, 1981-1985
• Jane Swift, Governor of Massachusetts, 2001-2003
• Michael E. Toner, Chairman and Commissioner, Federal Election Commission, 2002-2007
• Michael Turk, eCampaign Director for Bush-Cheney 2004
• Mark Wallace, U.S. Ambassador to the United Nations, Representative for UN Management and Reform, 2006-2008
• Nicolle Wallace, Assistant to the President and White House Communications Director, 2005-2008
• William F. Weld, Governor of Massachusetts, 1991-1997, and Assistant U.S. Attorney General (Criminal Division), 1986-1988
• Christine Todd Whitman, Governor of New Jersey, 1994-2001, and Administrator of the EPA, 2001-2003
• Meg Whitman, Republican Nominee for Governor of California, 2010
• Robert Wickers, Republican Political Consultant
• Dan Zwonitzer, Wyoming State Representative, 2005-present