Tough question. I honestly think it depends on the person. If you want my honest opinion, if I know someone on a personal level, and they are different from me politically or religiously, then I usually ascribe good intentions to them, even if we disagree. You can be a friend to someone through hard times, even if you are not the same political persuasion. If a friend's wife died, I wouldn't be concerned with how he was voting.
When I see politicians on my television saying that being gay is wrong and that global warming is a hoax, I tend to be less forgiving when ascribing motives. There's honesty for you! Take it for what it's worth.