CHICAGO — The legal skirmish over same-sex marriage shifted Tuesday to a federal appeals court in Chicago as attorneys for Wisconsin and Indiana sought to reinstate bans on gay weddings ruled unconstitutional two months earlier.

The outcome of the case also could directly affect hundreds of couples who were married in June after federal judges overturned the bans but before their rulings were put on hold pending appeal.

Gay marriage is currently legal in 19 states as well as the District of Columbia, and momentum is building for more states to recognize it. Advocates have won more than 20 court victories around the country since the U.S. Supreme Court struck down a portion of the Defense of Marriage Act that prohibited the federal government from recognizing same-sex marriage in 2013.

A voter-approved constitutional amendment bans gay marriage in Wisconsin. State law prohibits it in Indiana. Neither state recognizes same-sex marriages performed elsewhere.

Lawyers representing Wisconsin Attorney General J.B. Van Hollen and Indiana Attorney General Greg Zoeller were due to make oral arguments Tuesday morning to a three-judge panel of the 7th U.S. Circuit Court of Appeals. Attorneys for the American Civil Liberties Union and Lambda Legal, a national organization working for gay rights, also were scheduled to appear. Each side was allotted 20 minutes for arguments.