RE: Then WHY is it voted resoundingly down everywhere We The People are allowed to vote on it?
I wish I shared your optimism. in November 2012 Maine voted in favor of a law allowing same sex couples to marry.
In California, the percentage of those who are opposed to proposition 8 has been dwindling from a huge majority to a bare majority.
Such is life in a Socialist Democracy.
We've simply failed in explaining how homosexuality will make society worse. For that we need clarity on whether homosexuality is a mental illness, what makes a family strong i.e. a mother and father committed to one another and their children, and a disease vector showing just how unhealthy the homosexual lifestyle is e.g. suicides, drug/alcohol addiction/abuse, physical and mental abuse, disease, disease transmission and etc.
I suspect that support is thin and shallow, based on an abuse of the libertarian line "it's all OK for adults to do as they wish, as long as you're not hurting someone else". Plus, we've been shown the idealized homosexual, not the real ones. Show the hurt and pull back the curtain on the homosexual lifestyle the same way as has been done with abortion.
If people recognized just how self-abusive the lifestyle is they would reverse back just as quickly. Where are the conservatives showing just how few homosexuals really ever "marry" despite it being legalized in many states. In IL they don't even use the civil unions laws. This is an unnecessary change.