SurveyUSA writes that the prop 8 protests "have not changed many minds":

Of the those adults who tell SurveyUSA they voted FOR Prop 8, 90% of them told us recent rallies held by “No on Prop 8? Protesters have not changed their minds about the issue.  8% say protesters have changed their minds.

But an 8 percent swing among Yes on 8 voters would have made the difference. Imagine if we had run ads with gay couples in them and revealed our conviction before the vote. This campaign could have been won. Our bad.