Now that the primary vote is certified, we can know for certain how every area voted. And there are some definite geographic trends. The Seattle Times put all the data in a map, and it shows that Mike McGinn fared well in the city center (e.g. Capitol Hill, Central District, U-District) while Mallahan held down the neighborhoods on the edges and shores (e.g. Magnolia, Wedgwood, Laurelhurst).
Seattle neighborhood poster by Ork Posters
Greg Nickels, meanwhile, held down a handful of precincts--mainly in Southeast Seattle, a sliver of West Seattle, and South Lake Union. Meanwhile, James Donaldson picked up one one precinct in Rainier Beach, and Jan Drago, having failed to tap a surefire wellspring of Stallone-greased dollars, picked up none.