Yep, I was talking on a grand scale as well.
The people are the voters, and the voters often control what happens politically.
I know in a classroom, hair salon, or hang out with a group of friends, this argument won't sway that many opinions. But on a widespread, country scale, it could. It could make people not support groups like Mormons or Evangelicans or take an apathetic view to gay marriage. They may have their personal convictions opposing it, but they aren't gonna go out and vote against it.
Like I said, I think that's more an emotional thing rather than a rational one. Swaying an opinion is done by repeated positive contact with, in this case, gay men and women.

