Having done business with local governments around the country, I can tell you that the stereotypes about southerners or northeasterners are inaccurate. It's not like everyone from Georgia is a conservative and everyone from Massachusetts is a liberal. You find the same *kinds* of people everywhere, but in slightly different mixes.
Control of most states happens at the margins. If you have slightly more conservatives in a state, you get consistent conservative victories and if you have slightly more liberals you get consistent liberal victories. Incumbents tend to get re-elected too; that gives the ascendant fringe leverage over the low-information middle voters, and puts the weaker side in an up-hill battle for success. Lack of success for a minority party powerfully weakens that party, and it may have difficulty fielding strong candidates. Things tend to *look* hopeless after several decades of dominance by one party, but I think that's an illusion. A strong centrist candidate can win anywhere against a weak majority party candidate, as with Scott Brown who won the Ted Kennedy Senate seat in Massachusetts 2010.
Red states tend to have a history of hard luck and social upheaval, and this produces marginally more skepticism about government. By contrast Massachusetts, indisputably the bluest state in the nation, has enjoyed remarkable good fortune since the founding of the nation, and that produces *marginally* less skepticism about government here. But it's still there. In Massachusetts you still hear *exactly* the same range of opinions as you would in a red state. It's just that minority parties are structurally disadvantaged in states where one party has had a long record of success.
We just had a special election here to fill Ed Markey's congressional seat. The Democratic winner walked away with 65.9% to the Republican's 31.7%. That may seem like a landslide, but consider this. Almost a third of the voters came out for a totally unknown Republican, a political neophyte who nobody thought had a chance of winning against a well-known and popular politician. That strikes me as a remarkable showing, and I think it shows that even the bluest state is more purple than we imagine.