Legal Experts Concerned by Fed Prop. 8 Case

The suit is funded by the newly formed American Foundation for Equal Rights, a legal advocacy organization launched by political strategist Chad Griffin. A former communications staffer for the Clinton administration, Griffin has worked on political and social causes for Brad Pitt and Rob Reiner, among others in the entertainment industry. He declined to elaborate on the organization's board members or donors, saying that information will be provided in the coming days.

The success of any federal challenge to state bans on gay marriage largely depends on the future composition of the Supreme Court, said University of California, Los Angeles, law professor Erwin Chemerinsky.

"I've always believed that in my lifetime that the Supreme Court will rule that the denial of marriage equality violates the U.S. Constitution," Chemerinsky said. "The question is whether it's too soon to risk that the court will reject it. We don't know who's going to be on the court."

Should the liberal-conservative balance of the court remain unchanged in coming years, Chemerinsky predicted Justice Anthony Kennedy would likely cast the deciding vote in such a case.