MISSISSIPPI: A ban was approved in 2004 with support from 86 percent of the voters, the highest percent among all the voter-approved bans in the U.S. There's no expectation it will be repealed except under a mandate from Congress or the U.S. Supreme Court.
MISSOURI: A ban was approved in 2004 with more than 70 percent support; there's been no effort to repeal it. The state Supreme Court is currently considering a legal challenge to a law that limits survivor benefits for deceased public safety officers to spouses who were in a "marriage between a man and a woman." The case was brought by the same-sex partner of a former Highway Patrol officer killed by a vehicle while investigating an accident.
MONTANA: Voters approved a ban in 2004; it's not under immediate threat. But gay-rights advocates believe that parts of the Supreme Court rulings could bolster their arguments in a case seeking domestic partnership recognition. In that lawsuit, gay couples are seeking inheritance, joint tax and other legal benefits.
NEBRASKA: Voters approved a constitutional gay-marriage ban in 2000. In light of the Supreme Court rulings, gay-rights activists are now looking at ways to challenge it. Doing so would likely require a citizen initiative and another statewide vote, though supporters aren't ruling out a lawsuit to challenge the amendment in federal court.
NEVADA: Although Nevada is among the 29 states with a constitutional ban, it also has a domestic partnership law providing extensive rights to same-sex couples. Legislators approved a resolution this year aimed at changing the constitution to allow same-sex marriage; it will need a second round of legislative approval in two years before going to a popular vote. Meanwhile, there's a case pending in federal court challenging the constitutionality of the ban.
NORTH CAROLINA: The most recent of the nation's gay-marriage bans was approved by North Carolina voters in May 2012. Gay-rights activists are looking at whether the Supreme Court rulings provide an opening to challenge it.
NORTH DAKOTA: A ban was approved by voters in 2004 with 73 percent support. The GOP-dominated Legislature also has voted repeatedly against gay-rights measures, including a bill in the last session to prohibit discrimination based on sexual orientation in housing, public services and the workplace.
OHIO: Voters approved a ban in November 2004 after an expensive ballot campaign that some analysts say boosted turnout among supporters of Republican President George W. Bush's re-election in the battleground state. The new Supreme Court rulings fueled the hopes of FreedomOhio, a coalition of gay marriage supporters that's working to overturn the ban in 2014.
OKLAHOMA: More than 75 percent of voters approved a gay-marriage ban in 2004. Repealing it would almost certainly have to be done through court challenges, since there appears to be little appetite in the Republican-led Legislature to embrace gay rights. Last session, the House voted 84-0 for a resolution to reaffirm marriage as a union between a man and a woman,
OREGON: Voters in this relatively liberal state approved a constitutional ban on same-sex marriage in 2004 with 57 percent support. It's now viewed as perhaps the most likely state to overturn such a ban; gay-rights activists and Democratic politicians are gearing up to place a repeal measure on the 2014 ballot.
SOUTH CAROLINA: In 2006, 78 percent of voters approved a constitutional ban. Little has changed since then. There were no bills introduced in the Legislature dealing with gay rights in 2013, and legislative leaders don't expect it to be an issue any time soon.
SOUTH DAKOTA: Gay marriage has been banned since the Legislature passed a law in 1996, and the prohibition was strengthened with a constitutional ban approved by voters in 2006. Activists say there are no current plans to ask voters to overturn it.
TENNESSEE: Voters approved a ban in 2006 with 81 percent support. It appears under no immediate threat.