DENVER (AP) -- A New Jersey gay couple whose engagement photo was used in a Colorado campaign attack mailer says the image that once represented their commitment now makes them cringe.

The couple filed a lawsuit in Denver federal court against the group that used the photo without their permission and put it on mailers against a Colorado Republican state lawmaker who supported a failed civil unions bill.

The photo shows 32-year-old Brian Edwards and 37-year-old Tom Privitere holding hands and kissing with a New York City skyline as a backdrop.

The Southern Poverty Law Center filed a federal lawsuit Wednesday in Denver on behalf of the couple against Virginia-based Public Advocate of the United States.

Public Advocate president Eugene Delgaudio said in an email to the Associated Press that he is "looking into this."

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