NOM was organized by the Mormon officials and members to fight gay marriage in California and elsewhere. It has thumbed its nose at campaign disclosure laws in Iowa, Minnesota, New York, Maine, Rhode Island, Florida, California, New Hampshire, and Washington State all states which have sued or investigated NOM or in which NOM is suing or playing fast and loose with campaign disclosure laws because it doesn't want the public to know where it gets millions of dollars. NOM's chairman, Maggie Gallagher, has a history of unethical behavior which was covered by the Washington Post.
Here's video of Brian Brown, NOM's Catholic hood ornament, deflecting hard-nosed questions about NOM's finances in Washington, DC. Skip to 3:20 to get beyond his grandstanding.