Tom Privitere and Brian Edwards, a married couple living in New Jersey, said their engagement photo was altered from the original by the group, Public Advocate of the United States, which opposes gay marriage, in mailers sent during campaigning for Republican statehouse seats in Colorado.

Tom Privitere and Brian Edwards posed for their engagement photo, holding hands and kissing, in front of the Brooklyn Bridge in 2010. The image captured one of the happiest days of their lives. But earlier this year, their special moment was soured when the photo was used in two anti-gay mailers in Colorado.

On Wednesday, the couple and their photographer filed a lawsuit Wednesday in U.S. District Court in Colorado against Public Advocate of the United States, a nonprofit that opposes same-sex marriage. They are seeking a court order saying the group violated the law, damages, costs and attorney fees for the allegedly unauthorized use of the copyrighted photo.

“We want to take back the beautiful moment in our lives that was reflected in our engagement photo before it was hijacked,” Edwards, a 32-year-old college administrator living in Montclair, N.J., told NBC News on Monday before traveling to Colorado to file the lawsuit. “We also … want to take a stand for others who might be similarly targeted in the future.”

The couple, who met in New York in 2000, got engaged in December 2009. The next year in May, photographer Kristina Hill snapped their engagement photos. The pair married later that year in a civil ceremony in Connecticut.

“All that we did was what any other couple would do to mark their engagement and have these photos taken for family and friends to share our joy and our excitement and help people (see) what path we were taking toward our wedding,” said Privitere, 37. “It was a great, great day for us.”

Kristina Hill/Kristina Hill Photography This original engagement photo of Tom Privitere and Brian Edwards was taken on May 23, 2010. The couple married in Connecticut later that year.

The couple alleged that Public Advocate seized upon that personal moment to spread what Edwards called a “message of hate” in two mailers it sent this spring during Republican primary races for the Colorado statehouse.

One of the mailers targeted State Sen. Jean White, who supported a bill that would have granted same-sex civil unions. Across the couple’s image were the words: “State Senator Jean White’s Idea of ‘Family Values?’” The other one, aimed at House candidate Jeffrey Hare, read: “Jeffrey Hare’s Vision for Weld County?” Both candidates lost their races.

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A friend alerted the couple to the mailers in late June. It’s not clear how Public Advocate got the photo, which the pair had posted to a blog about their engagement and impending nuptials. They say the group never asked the couple or Hill to use it.

When contacted by NBC News for comment on the lawsuit, Eugene Delgaudio, president of Public Advocate, said in an email that he was looking into it but did not elaborate or provide further remarks.

“The use of Tom and Brian’s likenesses, or of Kristina’s copyrighted photo, was wholly gratuitous,” said their attorney, Christine Sun, of the Southern Poverty Law Center. “Public Advocate could have just paid for a stock photo of a gay couple kissing but instead Public Advocate decided to take this very personal photo of this happy moment and use it to attack gay people.”

“ … the doctrine of fair use is not intended to allow people to use copyrighted work just because it’s cheaper than paying for something,” she added.

The couple has experienced sleepless nights and anxiety since they learned of the mailer. They’re concerned about the impact of the mailers upon others who may have seen it, such as gay youth and their families who may be struggling with accepting them.

“Colorado is a positive step in trying to right a wrong,” said Privitere, who works in entertainment ticketing. “We’re nervous to be thrust into the public spotlight again. We’re nervous that we’re not going to represent our community the best that we can. But we’re going to do all that we can to try to fix or make this right.”

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