Marriage is essentially a word that was originally formed by religion. As a result, whenever someone talks about same-sex marriage, negative views come from those who are devout in their religion.
Due to the idea that the government should not support any religion or non-religion over another, the term for marriage should be changed to civil union.
Just as currently established, judges or specific individuals will have the authority to create civil unions. However, if a church wants to "marry" a couple, it is within their right to do so or not.
This way, all couples can have equal legal opportunities despite whether or not they are of the same gender. It removes the religious ramifications that people always argue because it's not based on religion. It's based on equality.