Scott McCoy, 40, and Mark Barr, 37, met 13 years ago when they were both twenty-somethings living in Manhattan. McCoy was a law student and Barr worked for Showtime.

McCoy landed a job as a clerk for a Utah Supreme Court justice and the couple moved to Salt Lake City in 2002. He became Utah’s first openly gay state senator in 2005 and served through 2009. McCoy and Barr, who recently earned a master’s degree in social work from the University of Utah, moved back to New York in June.

On Sunday, Utah’s Pioneer Day, they plan to marry at a city office in Manhattan. It will be their third commitment ceremony but their first legal marriage. In 2000, the couple wed in a religious ceremony on Bill Maher’s “Politically Incorrect” late-night show. In 2001, they obtained a civil union in Vermont.

“This will be different because it’s the real deal. It’s the full thing. It’s not a half measure,” Scott said. “Up to this point, when I talk about Mark, I talk about him as my partner. After Sunday, I will refer to him as my husband because that’s what he’ll be.”