Ron Brownstein is concerned that the Democrats could be permanently set to sea in a rising red tide.
His analysis is quite interesting. In the 100 fastest growing counties in America, Bush won all but about 4. Dole won 74 total. And, Bush won a lot of the areas with over 70% of the votes.
While the Democrats have the metropolitan areas, the Republicans are solidifying their hold on the exurban areas and rural areas, which are growing more than the metro areas.
A side benefit is that it makes GOTV easier when all of your voters are clustered together in a neighborhood AND it makes swing voters more likely to swing to the GOP. When all your neighbors have Bush signs in the yard, you might be inclined to go that way too.