While somewhat true on a broad base level, I feel like this greatly ignores a few things
1) Some of the more interesting regional differences. For example, many areas of the south ALWAYS elect Democrats to local positions, but NEVER to national ones. A democrat in Arkansas has a better chance of winning an election to be a state assemblyman or Governor then a republican... but senator? Not a chance.
2) The Cadre of "Have's" that have migrated to democrats do to conflicting goals. For example, Hospitals and Doctors tend to vote Democrat due to their conflicting interests with Insurance companies and because democrats often control the medicare pursestrings. Many Union Democrats, who are very much like white collar middle/upper workers both demographics wise and conservative values wise, but vote democrat because their bosses are republicans... and Big Banks, who tend to support democrats because deregulation in most areas actually causes them to risk losing market share to small banks. (John Corzine is a funny example. Big bank democrat who ran for Governor, ran a bank into the ground, and then was used as proof for why republicans and big banks are conspiring to screw America....)
3) I honestly can't remember what this third point was going to be... ah well.
