Thousands of opponents of Indiana Senate Bill 101, the Religious Freedom Restoration Act, gathered on the lawn of the Indiana State House to rally against that legislation on Saturday. Doug McSchooler/AP hide caption

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Tammy Brown, executive presbyter of the Presbytery of North Alabama, reads a proposed amendment to the Constitution of the Presbyterian Church (USA) on Feb. 21 at First Presbyterian Church in Florence, Ala. The amendment allows Presbyterian ministers to officiate at marriages of same-sex couples in states where that is legal. A majority of presbyteries have approved the measure. Kay Campbell/Landov hide caption

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Tori Sisson, left, and Shante Wolfe, right, exchange wedding rings during their ceremony, Feb. 9, 2015, in Montgomery, Ala. They were the first couple to file their marriage license in Montgomery County. Such marriage licenses appear to be on hold again following a state Supreme Court ruling on Tuesday. Brynn Anderson/AP hide caption

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Colleen Condon, left, and her partner Nichols Bleckley appear at a news conference in Charleston, S.C., in October, shortly after filing a federal lawsuit seeking the right to marry in South Carolina. A federal judge has ruled in their favor. Bruce Smith/AP hide caption

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Gay-marriage supporters follow an opponent of same-sex marriage in August, when four courts argued to preserve their bans on the unions in a federal court in Cincinnati. The court confirmed the states' bans. Al Behrman/AP hide caption

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Lynda Johnson (center) cries as she watches her daughter Kandyce Johnson (left) marry Jana Downs in Charlotte, N.C., on Monday. Same-sex couples lined up to get marriage licenses Monday, the first day Mecklenburg County issued the licenses. Jeff Siner/MCT/Landov hide caption

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Couples kiss during the Athens gay pride parade last June. Last month, activists organized a "kiss-in" during a church service run by a Greek Orthodox bishop who has threatened to excommunicate politicians supporting same-sex unions. Louisa Gouliamaki/AFP/Getty Images hide caption

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Gigi Chao (right) daughter of Hong Kong property tycoon Cecil Chao, poses with her partner, Sean Eav, at an event in Hong Kong. AP hide caption

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Virginia Attorney General Mark Herring speaks at the Virginia Capitol in Richmond on Dec. 18. Herring's announcement Thursday generated strong partisan responses. Steve Helber/AP hide caption

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Hawaii's Gov. Neil Abercrombie announced the special session on gay marriage at the Hawaii Capitol in Honolulu in September. The session will begin Monday, Oct. 28. Oskar Garcia/AP hide caption

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