My focus on the Mormon opposition to Same Sex Marriage led me to the site: http://lds4gaymarriage.org They are a group of Mormons that have examined their scripture and their conscience and found that although there may be scripture that condemns homosexual behavior, the denial of the right to marry is none of their business. I have not studied the Book of Mormon and can’t quote on my own authority but they did post this on their home page:
Joseph Smith said, "If I esteem mankind to be in error, shall I bear them down? No. I will lift them up, and in their own way too, if I cannot persuade them my way is better; and I will not seek to compel any man to believe as I do, only by the force of reasoning, for truth will cut its own way."
(Joseph Smith, Teachings of the Prophet Joseph Smith, selected and arranged by Joseph Fielding Smith [Salt Lake City: Deseret Book Co., 1976], 313.)