I heard an opponent of gay marriage say that they have to live by Christian morals. As a Christian, I am appalled by that statement. One's focus as a Christian is to be on Christ himself, not on us and a set of laws to live by. Christ died to free us from the law, that is to say, morals.
All a set of morals do, whether Christian or not, is to keep us looking at ourselves and constantly judging others for our failures. Jesus Christ died for all His children no matter their, race, gender or sexual orientation. Marriage is a right for all people.