To be honest, I don't really see the point of this tread. All states that have urban areas also have rural areas, and those are very different in terms of culture.
To that end, I think the most extreme is Illinois. In the 2010 gubernatorial election, Pat Quinn
only won Cook County and three other small, predominately African-American counties near the Kentucky boarder, and Bill Brady carried the other 98 counties. Yet Quinn still won. In 2014, Quinn only carried Cook county, and while he lost, he received 44% of the vote regardless.
http://en.wikipedia.org/wiki/Illinoi...election,_2014