When two baseball teams share a city, one of them dominates the geographic region with the city as its center. Greater New York, upper Jersey, lower CT like the Yankees, not the Mets. Northern California likes the Giants, not the A’s. In SoCal you won’t find many Angels fans outside Orange County itself. And the whole mid-northern Midwest, from Iowa across to central Indiana, roots for the Cubs, not the White Sox, whose fanbase consists of southern Chicago and a few adjacent suburbs.
(Go here for an amazing, data-rich, zoomable interactive of this NYT UpShot map, but be prepared to be depressed about how many Yankee fans there are freaking everywhere.)
Why? For NYC, LA, SF it’s pretty clear; one team is older and has a historic base that the other lacks. But for Chicago it’s less clear.
One friend suggested that Iowa has a, um, relevant ethnic similarity with the part of Chicago containing Wrigley Field. But Chicagoan tell me that the ethnic identification of White Sox fandom is historically Irish, not African-American.
My best guess is that it’s WGN, a mainstay of basic cable for decades which may have spread Cubs fandom across the nation the way TBS did for the Braves. But then one asks: in 1950, before TV, was there more parity between Cubs and White Sox fans? Who did people in Des Moines and Indianapolis (and for that matter Milwaukee and Minneapolis) mostly cheer for back then?
And what about New York, back when there were three native teams of about the same age? Did fans in Poughkeepsie and Rahway split evenly between Yankees, Dodgers, and Giants? What about the Phillies and the original A’s?