Those are the outer suburbs and exurbs, residential areas far from a major city.

NPR: Democrats Make Gains In A GOP Stronghold

And, as outer suburbs have proliferated, Americans have had to drive farther and farther to work, home or the shops.

ECONOMIST: Urban sprawl

Some communities in Washington's outer suburbs saw significant accumulation too, including in Loudoun County, which had 9 inches in some places.

NPR: Storm Strikes Mid-Atlantic; 250K Lose Power

It may also be slightly easier for Democrats to rally their troops: they tend to be concentrated in cities, whereas Republican voters are scattered in outer suburbs and the countryside.

ECONOMIST: The new rules of politics in a 50:50 nation

To hear the newspapers tell it, the sudden gain to the suburbs and the "outer boroughs" of New York City (that is, other than Manhattan) will be Wall Street's permanent loss.

FORBES: Rubbing elbows