I'm going with Kim's answer, this is about sexuality and not presentation. If the person with whom you have relations is of the same sex, then you are somewhere on the scale of homosexual or bi, no matter how dressed, IMHO. As for gay being to do with political persuasion, where did that come from? There are many examples of people from both left and right wing political persuasions that have either revealed or been exposed as gay. Happy to name them too if requested, but Peter Tatchell is normally your man for that in the UK.
Rebecca