Suprise! People who know homosexuals are more likely to favor letting homosexuals get married!
The idea, the logical jump we’re supposed to make, I suppose, is that personally knowing someone who is homosexual disproves all those scary boogeyman sterotypes we right-wingers like to promote (like, say, that homosexual behavior is exceptionally dangerous, to the practitioner, as well as others.)
I suspect the real reason is a combination of two factors. First, what Senator Moynihan famously described as “defining deviancy down.” Simply being exposed to homosexual behavior makes it appear more normal and acceptable, at least in the sense of how we mentally process information. Second, after you see what they’re capable of up-close-and-personal, do you want to be seen opposing these folks?
On a lighter note, have fun watching your liberal friends squirm when you point out Dick Cheney is to the left of President Obama on this one. Enjoy!