[1-Eagle]

Densely populated urban centers may need work, but our votes are traditionally in the small towns outside them.

[itsPatAmerican]

My thinking was this:
10% of a million is a lot higher than 95% of 30,000.
Urban areas are less Republican (my example is extreme) but there are still more Republicans per square mile, and therefore you'd do more good.

I'm not a strategist--but my back of the napkin calculations look good to me.