Yesterday, at the end of the first part of this post on exurbia and politics, I wondered how Mark Gersh/NCEC could come up with so many exurban counties (30) in a single state (Ohio). I don't know the full answer to this since Gersh's piece in Blueprint magazine includes no information on how he or NCEC define exurban counties. However, I did manage to get ahold of an earlier version of NCEC's criteria for typologizing counties and it indicates that pretty much any suburban county that does not contain a large city can be designated as exurban, if it is relatively downscale in terms of occupation, income and education or if it falls below a certain density criterion. (The current criteria apparently differ somewhat, but not by that much, from these earlier criteria.) This approach leads to a number of unusual results including:

1. Some entire MSAs (metropolitan statistical areas) are designated exurban, like the Canton MSA in Ohio and the Pensacola and Sarasota MSAs in Florida.

2. In other MSAs, only the county containing the MSA's main city is designated "urban-surburban" while every other county is designated exurban or even rural. For example, in the Columbus, OH MSA, only Franklin county is termed urban-suburban, while five other counties are designated exurban and two are considered rural. Similarly, all Ohio counties in the Cincinnati MSA are designated exurban except Hamilton county.

3. Medium-sized metro areas wind up being classified almost entirely as exurban or rural. In Florida, for example, there are 16 counties in medium-sized metro areas. Of these, just three are classified as either urban-suburban (1) or suburban (2), while 13 are classified as either exurban (11) or rural (2).

4. Almost no counties are simply designated "suburban". In Ohio, there are only three (compared to 30 exurban counties); in Florida, just five (compared to 21 exurban counties).

Gersh's article even refers to Hillsborough county, which contains Tampa, as exurban! (Note, however, that it is not displayed as such on his map of Florida, so perhaps his enthusiasm for exurbia was simply getting the best of him.)

This approach to defining exurbia is, in my view, simply too broad to be of much use. Collapsing all but the most urbanized parts of big metro areas, almost the entirety of medium-sized metro areas and outer suburbs everywhere into exurbia does considerable violence to the concept and clarifies little.

A geographer friend of mine comments as follows on the Gersh/NCEC approach:

The NCEC criteria don't have much to do with any accepted notion of exurban, since they ignore the geographic requirement of being on the fringe of metro areas. Many of the counties listed as exurban are independent small metro or micropolitan areas....It's "small urban" not "exurban".

In short, analyses like these create a big exurban problem for the Democrats by defining way more voters into that category than is really appropriate. By doing so, these analyses can say or imply "Democrats are losing because of those really fast-growing exurbs, so they are on the short end of the demographic stick!!" instead of the less exciting, but more accurate: "Democrats experienced some slippage in suburban and small urban counties of all types and that contributed to their loss in 2004". The task for the Democrats is the familiar one of getting enough garden-variety suburban and small urban votes back to win; they need not worry about being overwhelmed by a demographic tsunami of Republican exurban votes.