Hey Ivysaur, I just wanna say you seem like a really cool guy, reaching out to us religious people.
While I don't agree with gay marriage, I do agree that an open dialogue with each other should be started, if for no other reason than civility and understanding, instead of the hate that each side directs at each other.
I'm going to go out on a limb (wherein most of GAF will likely crucify me) and try and explain my side. When birth control became the norm in the '60s, there seemed to be no downside for religious folk: "Religious people don't have to have premarital sex. It just makes it safer for those who do." Now, I'm not against birth control. I use it myself with my wife. But something happened after it became widespread: waiting till marriage is now shunned. You're seen as a prude, an idiot, etc. if you believe in waiting till marriage. Why did this happen? Normalization. It happened because premarital sex, while it had existed before, became the norm. Therefore, people who believed it was morally wrong became shunned. It's scary for me to admit on a forum that I believe in waiting till marriage, for fear of being banned.
I'm in no way implying that gay marriage would become the norm. No, people's genes won't change just because the law does. But the current status of society is: "You can believe gay sex is immoral, but you have no right to stop someone from doing so." Which I agree with. I have no right to tell you what to do with your life. What people like me fear is that widespread gay marriage would make it wrong to think it's wrong; that we'll be shunned for holding the moral values we currently keep dear, even if we're not imposing it on anyone.
It used to be okay to be a virgin till marriage; now it's humiliating (I was one). It is currently okay to think that (without restricting anyone from doing it) gay sex is immoral, a fundamental belief in Christian chastity, but with the legalization of gay marriage that may not be the case.
The ironic thing is that we're worried about being shunned in the future, whereas you guys are fighting not to be shunned right now.
So I totally get where you're coming from, and why you're fighting the good fight. If nothing else, maybe my explanation of our fears can help you in your endeavors to spread what you feel is good, and to that I wish you all the best luck.