Sympathetic conversion by way of humanizing people is the way to go, I think, not forcing a position they disagree on them. When you take the role of the persecuted victim and allow others to see your pain, it makes it hard for them to turn a blind eye to your suffering.
I don't know about this part. There is something to it, in the sense that the polls seem to suggest association with gay people increases support for gay marriage. Although, I've also seen some claims that the people changed may be more likely to be liberals. So all else being equal (ugly assumption there), that will reach a limit.
I think that many people are easily moved to believe that their own local victimization is such a burden that it must be the first thing removed. Whether it's your toe, finger, or brain, every hurt feels very important. And various types of people are moved to react based on it -- even in cases where the "hurt" is more artificially construed. The major legislative barrier to gay marriage at present, after all, is called the "Defense" of Marriage Act. It implies that gay marriage would produce an injury, however symbolic, to previously conventional, hetero-normative marriages. We can find other cases, some involving arguably more legitimate grievances, where a political party won on claims of victimization and then itself did terrible things. If the primary platform is victimization per se
, then anyone who wants to oppose the movement will point to such things. It is important to point to actual grievances, but I think a movement needs to have some positive claims. Perhaps, it also needs to create situations where matters must be decided -- whether it's sitting in the "wrong" part of the bus, or going to court.
It can also be rather demeaning to suggest that a primary
source of identity/message should necessarily be evidence of injury. First, this makes it the duty of the most injured or vulnerable gays to be the most public and vocal. Second, opposing parties may seize upon that to insist that gays are doing pretty well in some ways. While it's not so representative, they could do things in response to mitigate the complaint such as say, pointing to a few fashion designers. They may also tell more conservative audiences that it was somehow a natural or religiously appropriate outcome for gays to be harmed. Which is to say that 1) again, the victim story may not affect conservatives and 2) gays will continue to suffer for lack of the benefits of marriage at the same time that some conservatives (among others) are being motivated to act on hate or discrimination -- these things multiply.