Not so. 16 of the 31 Democratic House pickups were in suburban districts. In fact, the Democrats carried the suburban House vote by a margin of 50-48 in 2006.
Note that I didn't mention anything about suburban/exurban or anyothersortofurban. I wrote "this sort of district"; affluent, white collar, well-educated, owner-occupied, and mostly made up of older (by American standards...) middle suburbs.
Demographically, MN-3 is very like IL-6, though a bit more bourgeois*.
Most, but not all, of those districts are very different to this one.
*No, I'm not a Marxist, but people would get the wrong end of the stick if I used the term "middle class"; which o/c means something completely different in the States than it does over here.