It's that time of year again: time to nod our heads at the fact that baseball fandom is largely geographic, unless you're a goddamned Yankees fan.
Definite second bananas in two-team metro areas, the Mets and Athletics don't take a plurality of any counties. (In other two-team markets, the Angels take a two-county swath of Southern California, and the White Sox actually win Chicagoland.)
But aside from fluke, small-sample-size exclaves, it's really only the Yankees that overspill their broadcast areas. Bandwagoning is a real thing, though. Facebook has created maps showing the spread of Giants and Royals fandoms since their pennant-winning seasons.