National Organization for Marriage

The National Organization for Marriage is an American non-profit political organization established in 2007 to work against the legalization of same-sex marriage in the United States. It was formed in 2007 specifically to pass California Proposition 8 prohibiting same-sex marriage in California. Wikipedia*

On the C-SPAN Networks:
National Organization for Marriage has hosted 1 event in the C-SPAN Video Library; the first program was a 2013 Rally.