There is a lot of talk about the terms we use within the debate regarding marriage rights. The word "Marriage" has a loaded cultural context given its quasi-religious and civil function. This has meant that in many ways each side is discussing two very distinct concepts. The choice has been between; on the right: a redefinition of "marriage," and on the left: a choice of partner that should not be infringed on by Government. I think the latter is the reality and the former is a paranoid delusion.
The left needs to realize that weak language won't help forward the cause of improving our countries record in terms of marriage rights. Like back when we changed gender charged titles from Fireman and introduced Firewomen. The weak language meant little in the way of positive change. Then someone decided that the stronger more modern "Firefighter" was the much better title. A wave of acceptance followed for more inclusive titles. Police Officer and Letter Carrier sound much bolder and important that the terms that they replace.
Now we need to frame marriage rights in much the same way. Marriage is a strong term but we lose some ground because it has a lot of religious baggage. The right relies on this baggage to create facile but easily proffered arguments. Civil Union is terribly weak language, although it does have the advantage of being more in line with reality. It addresses the license that is issued as opposed to the religious ceremony that is what sometimes follows.
I think that what might be better is to talk about the Marriage Contract. It is more legalistic and can be used as a hammer against haters. Along the lines of... We are not talking about marriage in the Baptist Church. We are talking about the Marriage Contract. Everyone should be able to enter into this contract with the individual that they choose. Rights are for the individual.
The right needs to understand that what we are discussing in terms of marriage rights is not their definition of the union of a man and a women but the right to choose whom you would like to wed. Their personal or religious beliefs should be strong enough to accept this, in much the same way we do not outlaw pork because of the Kosher or meat on Fridays because of the Catholics. The society needs to allow for a broader set of priorities and perspectives than their faith allows. This is the cost of the greatness that was given to us by the US Constitution.