A federal appeals court was set to hear arguments Wednesday in six gay marriage fights from four states — Kentucky, Michigan, Ohio and Tennessee - in the biggest such session on the issue so far.

Three judges of the 6th U.S. Circuit Court of Appeals in Cincinnati will consider arguments that pit states' rights and traditional, conservative values against what plaintiffs' attorneys say is a fundamental right to marry under the U.S. Constitution. Large demonstrations are expected outside the courthouse by both opponents and supporters.

Michigan's and Kentucky's cases stem from rulings striking down each state's gay marriage bans. Ohio's case deals only with the state's recognition of out-of-state gay marriages, while Tennessee's is narrowly focused on the rights of three same-sex couples.

Attorneys on both sides in the Michigan and Ohio cases will go first and get a half-hour each to make their cases. Kentucky and Tennessee will follow, with 15 minutes for each side from both states.

A handful of people were at the courthouse Wednesday before it opened to reserve a seat in an overflow room for the hearing, including Frank Colasonti Jr., 61, of Birmingham, Michigan, who said he camped outside the building overnight.

Colasonti said he and his partner of 26 years married this year in Michigan, before a court order halted marriages pending the state's appeal.