Here’s what David Grosso’s victory over Michael A. Brown looks like, geographically speaking. In a pattern similar to the 2010 mayoral primary, the 2011 at-large special election and the 2012 at-large Democratic primary, the split was stark between western and eastern wards. This time, however, the candidate preferred by the western wards  (1,2,3,6) triumphed.

The ward splits are below. Not included are other candidates, including Democrat Vincent Orange, who out-polled his competition in every ward except 2 and 3, where Grosso beat him.

(Election Day results from D.C. Board of Elections)

Overall, Grosso beat Brown in 74 of 143 precincts — not an overwhelming showing on its face, but Grosso’s average margin in his precincts was 505 votes versus Brown’s 280 votes.

Here are the five precincts where Grosso tallied the largest margins over Brown:

Precinct 51: Ward 4/Chevy Chase North. Grosso +1,754
Precinct 34: Ward 3/Cleveland Park North. Grosso +1,300
Precinct 89: Ward 6/Eastern Market. Grosso +1,205
Precinct 33: Ward 3/Tenleytown East. Grosso +1,159
Precinct 32: Ward 3/Friendship Heights. Grosso +1,118

And here are the five precincts where Brown racked up the biggest margins over Grosso:

Precinct 110: Ward 7/Hillcrest/Fairfax Village. Brown +642
Precinct 125: Ward 8/Washington Highlands West. Brown +638
Precinct 66: Ward 5/Fort Totten. Brown +552
Precinct 116: Ward 8/Shipley Terrace. Brown +542
Precinct 126: Ward 8/Bellevue South. Brown +504

And then there’s all-important Ward 4, which turned out not to be much of a difference-maker this time. Even if Brown had managed to get his 2008 figure of 13,500 votes there, rather than the 9,000 votes he did get, it wouldn’t have made much of a difference. But he did lose more votes there versus 2008 than any other ward in the city.

While he beat Grosso in 12 of 20 precincts there, Grosso won roughly 200 more votes thanks to his overwhelming margins in the two west-of-the-park precincts (51 and 52). But also note Brown’s poor showing in key east-of-the-park Precinct 62, where he stands 42 votes short of Grosso. That precinct votes at Shepherd Elementary School, where Brown attended grade school.

UPDATE, 2:30 P.M.: Here’s another map, showing the areas where Brown lost the greatest percentage of votes from 2008 to 2012. He gained votes in only two places: Precinct 131 near Nationals Park, which has seen extreme population growth, and Precinct 100, in Ward 7’s Mayfair neighborhood.