The question was not directed at me but I can answer it easily.
I believe a legal marriage in the United States should be one man and one woman. The definition of marriage has been a union between a man and a woman for all of recorded human history even when polygamy was the norm.
The purpose of marriage has always been to establish familial bloodlines and presumes that there could be children. It creates a legal bond that protects both the married couple and any children produced from the union as well as right of inheritance, ability to make decisions for an incapacitated mate, visitation rights, etc.
As a gay union establishes no familial bloodlines and does not presume that there could be children, in my opinion it is not a marriage. In general gay unions do not produce the same benefits to society that traditional marriage does though reasonably gay people who establish unions intended to be permanent do need some accommodation by society.
I do think the law should provide necessary protections for gay couples--right of inheritance, visitation rights, right to make financial or healthcare decisions for an incapacitated mate, etc. But don't call it marriage. It isn't. Give it its own designation.
As a society the many should not have to change their culture to accommodate a very few other than to protect the unalienable rights of all. The very few should have to accommodate and adapt to the culture of the many.