Meg Whitman and Jon Huntsman are among the Republicans signing a legal brief in support of gay marriage.

According to The New York Times, the brief will be submitted this week to the Supreme Court in support of a suit challenging the constitutionality of Proposition 8, California's 2008 voter-approved constitutional amendment limiting marriage to heterosexual couples.

Passage of Proposition 8 put an end to the weddings of gay and lesbian couples taking place in the state after the California Supreme Court legalized such unions.

The Supreme Court will hear arguments in the case next month and is expected to hand down a ruling in June.

Evan Wolfson, founder and president of Freedom to Marry, applauded the 75 Republicans who as of Monday had signed on to the brief.

“A who's who of the Republican Party has come before the Supreme Court to affirm that support for the freedom to marry is a mainstream position that reflects American values of freedom, family, and fairness, as well as conservative values of limited government and personal responsibility,” Wolfson said in a statement. “As opposition to the freedom to marry becomes increasingly isolated and the exclusion from marriage increasingly indefensible, Americans all across the political spectrum are saying it's time to end marriage discrimination, do right by families, and get our country on the right side of history.”

Whitman, the president and CEO of Hewlett-Packard and the fourth wealthiest woman in the state of California, lost her 2010 bid to run California to Governor Jerry Brown. She has previously supported Proposition 8.

Huntsman, a former governor of Utah who ran for president last year, recently switched from backing civil unions to full marriage.

(Related: Jon Huntsman urges Republicans to embrace gay marriage.)

Also signing are Representatives Ileana Ros-Lehtinen of Florida and Richard Hanna of New York; David A. Stockman, President Ronald Reagan's first budget director; and Deborah Pryce, a former House member.

“Like a lot of the country, my views have evolved on this from the first day I set foot in Congress,” Pryce told the Times. “I think it's just the right thing, and I think it's a solid legal footing, too.”

Tom Goldstein, publisher of Scotusblog, said the brief “has the potential to … make a real difference” in the case.

“The person who is going to decide this case, if it's going to be close, is going to be a conservative justice who respects traditional marriage but nonetheless is sympathetic to the claims that this is just another form of hatred,” he added. “If you're trying to persuade someone like that, you can't persuade them from the perspective of gay rights advocacy.”