Wow... I'm floored.
Bob Barr, the author of DOMA, argues for it's repeal, and in favor of same-sex marriage, and from a largely libertarian perspective, here.
I also didn't realize that Mr. Barr's purpose in authoring DOMA was pro-Federalist, rather than anti-gay, at least if one takes him at his word. Since I don't know the man, I'm forced to do exactly that, especially when he argues that, because the laws consequences were opposite to his purposes in writing it, it should be repealed.
He also argues that marriage, as a whole, should be reduced to a simple matter of contract law, with no more government involvement than in any other contract between parties.
I concur.
Solemnizing interpersonal relationships is not a proper function of government. Dealing with the consequences of those relationships, not least property rights and child custody, is, but that can be adequately handled by contract law, without carving out an entirely new area of the law to deal with those contracts that are called "marriages."
Yes, society needs some mechanism of formalizing the obligations that couples undertake when they align their lives, as well as of enforcing those obligations down through time. It is by no means clear that there is a special category of interpersonal obligations that requires a special area of the law, with rules about who can and cannot enter into said obligations.
So, a phrase I never thought I'd say...
Right on, Bob Barr.
--Shannon