According to [link|http://www.msnbc.msn.com/id/4496265/|polls], about half the country doesn't want civil unions of gays either. And the people who are against it are more likely to turn out at the polls than the people who are for it.
Of the 11 states that just banned gay marriage, 2 of them (Georgia and Ohio) banned gay civil unions as well.
As for whether marriage is a primarily religious institution, we've disagreed on this before. I think that it is not. You know why I think that, I know why you think otherwise, and we each think that the other person is wrong. That isn't about to change.
Cheers,
Ben