South Dakota and 33 other states do not recognize same-sex marriage. But that number has declined from just a year ago as judges in several states — including Utah, Oklahoma, Virginia and Texas — have struck down state bans as unconstitutional. A judge in Kentucky overturned part of that state's ban; Kentucky must now recognized same-sex marriages from other states.

Most of those rulings are being appealed and have not yet taken effect.

Earlier this month, a lawsuit filed in Wyoming challenged that state's gay marriage ban and refusal to recognize such marriages from other states, according to the Casper Star-Tribune.

State marriage licenses give couples access to a variety of special benefits, according to GLAAD, a gay and lesbian advocacy center. The organization says these rights include automatic inheritance, child custody and hospital visitation rights, medical decision-making powers, access to family insurance policies, standing to sue for a spouse's wrongful death, and immunity from having to testify against one's spouse.