S. T. Karnick has written a piece for Salvo Magazine that is worth reading.  It may be the most reasonable appeal to the Same-Sex Marriage camp I've ever read. 

The issue, it’s important to remember, is not whether society will allow homosexuals to “marry.” They may already do so, in any church or other sanctioning body that is willing to perform the ceremony. There are, in fact, many organizations willing to do so...

No laws prevent these churches from conducting marriage ceremonies—and nearly all Americans would agree that it is right for the government to stay out of a church’s decision on the issue. Further, any couple of any kind may stand before a gathering of well-wishers and pledge their union to each other, and the law will do nothing to prevent them. Same-sex couples, or any other combination of people, animals, and inanimate objects, can and do “marry” in this way. What the law in most states currently does not do, however, is force third parties—individuals, businesses, institutions, and so on—to recognize these “marriages” and treat them as if they were exactly the same as traditional marriages. Nor does it forbid anyone to do so.

In short, individuals, organizations, and institutions in most states are currently free to treat same-sex unions as marriages, or not. This, of course, is the truly liberal and tolerant position. It means letting the people concerned make up their own minds about how to treat these relationships. But this freedom is precisely what the advocates of same-sex “marriage” want to destroy; they want to use the government’s power to force everyone to recognize same-sex unions as marriages whether they want to or not.

No doubt many will not find this article persuasive.  But consider why.  I have a feeling that it is because Same-Sex Marriage advocates think that Same-Sex Marriage is morally acceptable (even virtuous), and that it is morally obligatory for everyone to recognize it.  But this is not the argument that the "No on 8" crowd is making.  Their argument is based on the premise that gay couples are somehow being barred from marrying (which is untrue) and that the moral issue at stake is one of freedom of choice, tolerance, and liberty.  But as this article adeptly points out, it is the radical Same-Sex agenda that is now threatening true freedom of choice and tolerance. 

Read the rest of the Salvo article here.