Lifelong Republican Ted Olsen—who is suing to overturn Prop 8 in federal court—makes the case in Newsweek:

Many of my fellow conservatives have an almost knee-jerk hostility toward gay marriage. This does not make sense, because same-sex unions promote the values conservatives prize. Marriage is one of the basic building blocks of our neighborhoods and our nation. At its best, it is a stable bond between two individuals who work to create a loving household and a social and economic partnership. We encourage couples to marry because the commitments they make to one another provide benefits not only to themselves but also to their families and communities. Marriage requires thinking beyond one's own needs. It transforms two individuals into a union based on shared aspirations, and in doing so establishes a formal investment in the well-being of society. The fact that individuals who happen to be gay want to share in this vital social institution is evidence that conservative ideals enjoy widespread acceptance. Conservatives should celebrate this, rather than lament it.

Or as I advised social conservatives in The Commitment: take the fucking compliment already. We who are about to suck cock salute thee!