Gay marriage is about equal rights.
Then argue your support for this belief.
I do not dispute that marriage bestows rights above an beyond unmarried individuals...
Oh, you dont intend to do that. You intend to just declare that its about equal rights in spite of being forced to admit that it isn't. Equal rights is not a slippery concept. It is an absolute. Either rights are equal for all people are they are not equal rights.
Denying individuals the ability to participate in this institution simply because of sexual preference...
Sexual preference is not and never has been a requirement or limitation of marriage in this country. You seem to be equating sex with marriage, a quite arbitrary definition.
Can I marry my mother? I don't intend to have sex with her. I just wish for her and I to join the special rights club that gays want to so badly be in. Whats that? There is no push to legalize marriage between mother and child? Yeah... because its not about equal rights.