I read comments, made by attorneys for individuals who are suing for the right to same-sex marriage, indicating that individuals have a "constitutional right to marry" and a federal judge's comment, that marriage is a "fundamental right."
In my reading of the Constitution, I don't see where individuals are granted the "right" to marry. Marriage isn't a constitutional right, neither is it a fundamental right. It's a privilege granted by government according to legislation that is enacted by representatives of the citizens. The government determines who may marry, at what age, the fees required, who must perform the marriage and other stipulations. Couples don't have the right to be married, but they may be granted the privilege to marry when they comply with the laws of the land. If they don't comply with the law, they don't have a legitimate right to those privileges.
In my opinion, state legislatures should retain the fundamental constitutional right to listen to the voice of the people and determine what is best for their citizens in the important question of who is allowed to marry.