I live in an 80% Obama precinct because college campus. The generalizations in this thread just aren't realistic.
There are >80% Obama precincts on the south side of Chicago, for example Englewood with crime rates through the roof. There are >80% Obama precincts in Highland Park IL, one of the richer towns in the Midwest that also happens to have a huge Jewish population.
There are >80% Romney precincts in downstate Illinois that are rural swaths. There are >80% Romney precincts in North Barrington IL, which is a very nice, wealthy, exurban community.
Is North Barrington the same thing as regular Barrington? Because there are like ten of them and I've only ever heard of Barrington (which is close to where I live), South Barrington, and Lake Barrington