WATCH: Colo. Vets Come Out for Marriage Equality

As the nation turns its eye to the federal appeals court in Denver, which is expected to rule on a case challenging Oklahoma's ban on marriage equality in the coming weeks, advocates have launched a new 30-second ad on TV stations statewide highlighting some perhaps surprising support for the freedom to marry.

The newest ad from Why Marriage Matters Colorado, a pro-equality campaign by state and national organizations, features three military veterans -- and one openly gay active-duty Air Force master sergeant -- explaining why they support the freedom to marry.

Together, the four men have dedicated nearly nearly five decades to military service -- and straight veterans Army Staff Sgt. Izzy Abbass, retired U.S. Air Force Senior Master Sgt. Dennis Mont'Ros, and former Marine Sgt. Will Glenn believe their comrade deserves the same freedom to marry that they enjoy.

Master Sgt. T. Ashley Metcalf served in both Afghanistan and Iraq and is still serving in the U.S. Air Force, stationed at Buckley Air Force Base in Aurora, Colo.

"I've been married for eight years, going on nine, happily married" says Abbass in the ad. "And why shouldn't Ash, a good friend of mine, be afforded that same opportunity? He should have the same freedoms we have -- and that includes the freedom to marry."

Speaking with Denver's KUSA, Abbass says he hopes the ad will help Coloradans rethink opposition to marriage equality -- although recent polling suggests that a majority of Coloradans support the freedom to marry.

"My biggest hope is that people will think about the men and women who serve this county and say ... you know what? If they're good enough to [fight for this country,] they're good enough to have full, equal protection," Abbass told KUSA.

The ad began airing on networks statewide Monday evening, just one week before a decision is expected in the federal appeals case challenging Oklahoma's ban on same-sex marriage, which was argued before the 10th Circuit Court of Appeals in Denver last week.

Watch the ad below.