++Addition++Agnostic shows that the political money divide correlates as strongly (slightly more so, actually) with median income (.38) as it does with McCain's total support in the state. Race plays an important role in both of these relationships. Fortunately, the exit polling provides data for whites by income, although not as detailed as the numbers for all races. I will see how the money divide looks if only whites are considered.
[Thanks to MWC for catching an elementary mistake on my part that originally had Utah's figure calculated incorrectly. It's been fixed, and I've removed the embarassing gaffe, but it's still traceable in the comments for the saddists among you!]
Intrigued by Razib's review of Red State, Blue State, Rich State, Poor State, but having decided to put it on the Christmas list, I might be flying blindly here. Razib writes:
To a first approximation the rich tend to vote Republican, the poor tend to vote Democratic, the old stereotype holds. But there is also the reality that the wealthier states tend to vote Democratic and the poorer ones tend to vote Republican. ...The data used are from the '08 election, so if anything it at least offers a look at the extent of continuity in a trend identified in the book, looked at from a bit of a different angle. Honestly, I'm not sure where to go with what follows, but since it's been gathered and might be found useful to some people, a table is presented below.
The rich in Connecticut, the wealthiest state per capita, are not much more Republican than the poor. In contrast, the rich in Mississippi, the poorest state, are much more Republican than the poor. Ohio, a middle income state, is somewhere in the middle. What Gelman et al. are showing here is that looking just at states removes critical information; class is a much better predictor of political orientation in poor states than it is in rich states. It isn't that rich states are blue because they are rich, it is that in rich states income doesn't matter much in relation to politics.
The larger the political money divide was, the more strongly the state on the whole backed McCain. The correlation among the two is a moderate .35 (p=.01).
As the book predicts, wealthier states see less of a partisan economic split than poorer states do. Per capita gross state product and the political money divide correlate at .26 (p=.06). But that's without taking cost of living into account, which would surely attenuate the already weak correlation, as blue states are generally more expensive places to live than red states are. So more than poorer states seeing an accentuated political money divide, it is Republican states that do.
The political money divide is computed by taking McCain's proportional support among those earning more than $100,000 a year and subtracting his proportional support among those earning less than $50,000 a year. This was done in part because more precise income brackets lacked sufficient sample sizes in several states, while said breakdowns were available for every state. So if McCain earned 68% of the $100k+ vote and 47% of the $50k- vote, the political divide is 21 (68-47). That's the portrait of a state (North Dakota) divided pretty sharply along economic lines. States like these tended to go for McCain. Oregon represents the only state in which the political money divide is negative (that is, those making $50k- were very slightly more likely to vote for McCain than those making $100k+ were). Whiter states like these tended to back Obama.
This surprises me a bit because egalitarianism at the state level is marginally good for Republicans (the correlation between the income ratio of a state's top 5% of earners and its bottom 20% of earners and McCain's level of support is an inverse .12, p=.21).
Following is a ranking of states based on the political money divide as previously defined:
|District of Columbia||5|
My first thought is that this proxies fairly well for a state's level of social conservatism. Parenthetically, if anyone is aware of a decent state ranking by level of social conservatism, please alert me to it. Race--specifically the relative size of a state's black voting population--is also important (the two correlate at .45, p=0), a point that is hardly startling when it is recalled how black folks 'push' whites towards the GOP.
* Utah is the sole exception to the earlier assertion that data by the aforementioned income brackets are available for all states. The $100k+ breakdown is not reported, but by working backwards from the $50k- and $50k-$100k yields 81% support for McCain among the 17% of Utah voters bringing in more than $100,000 per year.