Perhaps counterintuitively at first, divorce rates also correlate strongly with voting Republican at the state level (r = .53, p = .00). That's surely not something that red state "values voters" are proud of, is it? Well, the confounding factor is that divorce rates are measured among the population at large, not just among those who are (or were) married. So in states where relatively few people get married, it's not surprising that divorce rates are going to tend to be lower there than in states where more people tend to get married. Indeed, marriage and divorce rates correlate with one another at .39 (p = .01) at the state level.
How about an attempt at measuring the durability of marriages by looking at the divorce rate in the context of the marriage rate? The following table ranks states in this way by taking the number of marriages per 1,000 people aged 15 and older that occurred in 2009 and dividing it by the number of divorces per 1,000 people aged 15 and older that occurred over the same period of time. So it's not measuring the healthiness of 'the institution of' marriage per se*, but instead how committed those who actually get married tend to be:
|2. North Dakota||3.34|
|6. District of Columbia||2.81|
|9. New York||2.55|
|10. New Jersey||2.43|
|14. South Carolina||2.23|
|24. North Carolina||2.06|
|25. West Virginia||2.04|
|30. New Mexico||2.00|
|39. South Dakota||1.84|
|48. New Hampshire||1.65|
|49. Rhode Island||1.60|
There is a bit of a generational issue here, as we're gauging to some extent how eager relatively young people are to get married with how likely older married people are to get divorced. Theoretically, younger people in a given state who are getting married today could be entering into much stronger (or weaker) marriages than their divorcing parents did when they were married compared to what is taking place in another state could make states where marriage is suddenly getting much stronger or much weaker stand out less with the old strength (or weakness) negating the new weakness (or strength). Or, the marriage rate in a state may be undergoing a major shift, with relatively few (or more) of its younger people getting married compared to what has taken place in the state's past. It's difficult to account for these differences, although states undergoing the most demographic changes are the most likely to be effected.
There aren't any clear correlations with things like political leanings or IQ that emerge (both are statistically insignificant, with only slight positive relationships existing with higher IQ and voting Democrat), as this accompanying map illustrates. Mountain states tend to do the best, while the upper Northeast and South fare the worst.
I suspected that among states where marriage rates are higher matrimony would be more superfluous than in states where fewer people get married in the first place, as if the relatively few people who actually do get married in states like Maine and Rhode Island actually mean it, whereas in states like Wyoming where everybody ties the knot, there are plenty of marginal people with lots of slack in their strings. Not so, however--the correlation between the marriage rate and marriage durability at the state level is a healthy .52 (p = .00). Marriages tend to be more durable in states where more people get married in the first place.
* In DC, for example, the marriage rate is on the low end among all the other states, but the divorce rate is the even further down the list, second from the bottom. Consequently, marriage durability in the nation's capital is actually quite high.