I agree with you. I am actually surprised there aren’t more of these 0 Romney vote precincts. In the inner cities of crime-ridden locations, there is probably not a single Republican voter. That is not hard to believe. It would actually be more surprising if you found a single R voter there...
I disagree. Statistically, it is highly improbable that, taken as an aggregate, that there wouldn’t be at least one vote (error or otherwise) for Romney.
100% is extremely unlikely, even with a homogenous demographic.