Should cat-owners be allowed to enter their cats in a dog show?
According to the foundational appeal to definitive propriety in any such question, the answer is, obviously, no.
Likewise, since marriage is what it is -- between a man and a woman as husband and wife -- again with respect to definitive propriety, the question itself is ludicrously stupid, and the answer is again, obviously, no.
Polygamists can have their own-named civil union domestic partnership, legally recognized by government and private enterprise, calling it polmarriage or whatever, but they can't call it marriage, because that civil union domestic partnership is already pre-defined for over 12,000 years and legally pre-named as being what it is -- between a man and a woman as husband and wife.
It never ceases to amaze me how pre-conceived ideology, left, right, or libertarianly schizoid, can so greatly dumb down its sufferer to the degree that the obvious is rendered nebulous to them. :roll: