Since legislation like DOMA is no longer the law of the land in the US, conservative evangelicals are now turning their opposition against all forms of poly relationships. They do so at their own risk of course, since eventually their own belief in the infalability of scripture as the basis of life and belief, will be turned against them.
I try to love my wives this way, unconditionally! Husbands love your wives, even as Christ loved the church, and gave himself up for her. Eph. 5:25