While supporters of the Defense of Marriage Act (DOMA) are quick to point out that it won bipartisan support in Congress and was signed into law by a Democratic president, they neglect to mention that many of those lawmakers have since had a change of heart.

The law which forbids federal agencies from recognizing the legal marriages of gay and lesbian couples and allows states to ignore such marriages performed in another state was written by former Georgia Congressman Bob Barr, a Republican turned Libertarian.

In 2009, Barr came out against the law he authored.

“It truly is time to get the federal government out of the marriage business,” Barr wrote in an op-ed published in the Los Angeles Times.

Barr argued that DOMA had run afoul of the federalist principle of states' right to self determination because it only protects those states that don't want to accept the marriages recognized by another state. It is “one-way federalism,” Barr wrote.

Furthermore, Barr argued, the law punishes those states that do choose to grant marriages or civil unions to gay couples by invalidating those unions on the federal level.

“[T]he heterosexual definition of marriage for purposes of federal laws – including, immigration, Social Security survivor rights and veteran's benefits – has become a de facto club used to limit, if not thwart, the ability of a state to choose to recognize same-sex unions.”

“Even more so now than in 1996, I believe we need to reduce federal power over the lives of the citizenry and over the prerogatives of the states,” Barr says. “If one truly believes in federalism and the primacy of state government over the federal, DOMA is simply incompatible with those notions.”

Former President Bill Clinton has said his position on gay marriage was “wrong.”

In 2009, he told CNN's Anderson Cooper that he now supports gay and lesbian couples marrying.

“I think it's a good thing not a bad thing. And I just realized that, I was, probably for, maybe just because of my age and the way I've grown up, I was wrong about that.”

“I just had too many gay friends. I saw their relationships. I just decided I couldn't, I had an untenable position,” he added.

Other Democratic lawmakers – including Senators Patrick Leahy of Vermont, Tom Harkin of Iowa and Charles Schumer of New York – have also revered course on the issue.

On Wednesday, House and Senate Democrats introduced legislation that would repeal DOMA.