The National Organization for Marriage (NOM) on Tuesday lost an appeal to keep its donor list secret, the AP reported.

NOM poured nearly $2 million into the 2009 fight to repeal Maine's gay marriage law.

But the group has refused to abide by the state's campaign reporting laws, which say groups that raise or spend more than $5,000 must disclose donors who make contributions in excess of $100.

NOM has previously argued that Maine's laws are overly burdensome and unconstitutional.

“We already know that the homosexual lobby has launched a national campaign of harassment and intimidation against supporters of traditional marriage, so there's good reason to keep these names confidential,” NOM lawyer James Bopp Jr. told the AP.

Gay marriage activists have previously alleged that NOM's financial support comes mostly from religious groups.

“They [the Mormon Church] have created front groups that can do their bidding in banning same-sex marriage throughout the United States. The Mormon Church gave $1.2 million to ban gay marriage in Alaska and Hawaii, and got caught. Ever since they work through front groups to try and hide their direct involvement,” said Fred Karger, founder of Californians Against Hate.

NOM said it would appeal the ruling by the First Circuit Court of Appeals in Boston to the U.S. Supreme Court.