I am a little confused as to what you mean with regard to my comment about cities.
As I see it, urban environments tend to cultivate more left-leaning voters for a number of reasons. First is that Democratic policies tend to lend themselves to more urban living. Second, cities have higher concentrations of young voters, which generally shifts the overall politics to the left. Most importantly, though, would be that people overwhelmingly vote the same as their families. If your parents voted Democrat for any of the reasons I mentioned above, chances are you will too. This is the same reason why there are still a few pockets of the deep South that will always vote Democrat.