States don't marry people, churches do. When a couple goes before a justice of the peace and get married, they're really just entering a civil-union. The state has allowed religious officiants to create these unions as part of a church's marriage ceremony, but they are two distinct institutions. For instance if one get's married in the Catholic church, and later gets a civil divorce the church still views that person as being married. In order to get remarried in the Catholic church, you have to have the first marriage annulled by the church. Conversely, just having one's church marriage annulled doesn't leave one legally eligible for remarriage until they get a civil divorce.
Of course the source of confusion is that the state refers to civil unions with the religious term marriage. When people hear about gay marriage being legalized, in their minds they think of the religious part of it, and no one likes the state messing around with their religion. If gays are allowed to get married, no church is obligated to marry them. There are plenty of churches that will (some already do) but the state can't mandate that a church violate its religious beliefs.
Gays need to drop the gay-marriage campaign, and go for civil-unions which are identical, yet more palatable to the general(voting) public.
