There is a stereotype of there being one specific evangelical Christian view on same-sex relationships and behaviour. However, this is not the case as there is a debate between groups of evangelicals that support or are indifferent to same-sex issues and those whom take the anti same-sex view.
The biggest difference in view tends to be amungst younger v. Older believers. However, this could be data collection bias as well. For example; the Evangelical Lutheran Church has an entire policy which is welcoming of LGB peoples. Also, reports are biased against any evangelicals that never were given a chance to participate in them.
I support LGB marriage and also am a defender of the importance of marriage for creating the most stable environment to raise children in. I agree that a family of married biological mother and father is the optimal form of raising a family. However, for the LGB person it is better to extend the sacred union to include them than to exclude them.
I do think that children should have strong role models from an early age of both mother and father figures even in a same-sex marriage. There should be in the life of the child if one is in the marriage role models of both sexes even if it is just a family friend. Someone to be the substituted figure of both father and mother.
I also do not condone all same-sex behavior under all circumstances. I do think that there needs to be standards irregardless of which sex you are with.
I also need to say that I do not have any ill will towards evangelicals that disagree with same-sex marriage or behavior. I love my traditional only Brothers and Sisters in Christ as I love all the non believers in my life. Just like I do not wish for my non-reconciliarion Brother or Sister to go through hell on Earth because they have mistranslated English Bibles.
At the end of the day we should all be able to get along and agree to disagree both the believer or atheist. We should not need to go along (agree) to get along in Agape Love for each other.