San Francisco in a rout

This story is part of ESPN The Magazine's Oct. 14 Bay Area Issue. Subscribe today!

AS ONE of just two regions in the country that's home to two baseball and two football teams, the Bay Area has deep-seated sports rivalries. But when it comes to residents' fandom, there's no contest between San Francisco's 49ers and Giants and Oakland's Raiders and A's. We asked Facebook to tally up the number of likes for each of the four teams in every one of the Bay Area's 162 towns, creating the most detailed and accurate fandom map ever. The result? A sea of orange and red.

1. Tiny Elmira (population 188) was the only town out of 162 in the Bay Area where A's fans outnumbered Giants loyalists.

2. The A's are winning on the field, but they can't even win the loyalty of their own hometown. Two-thirds of Facebook-liking Oaklanders call themselves Giants fans.

3. Wealthy Marin County had some of the highest rates of Giants partisanship even though its largest city, San Rafael, is nearly equidistant between the Giants' glitzy stadium and the decrepit one the A's play in. In six Marin County towns (and 16 overall), not a single person liked the A's on Facebook.

4. The East Bay is typically thought of as Oakland territory, but the Facebook data doesn't back that up. Seventy-nine percent of Orinda residents favored the Giants ... perhaps in part because Giants superstar Buster Posey just bought a house there?

5. Just a few miles down I-880 from the O.co Coliseum, Ashland is evenly split between A's and Giants fans.

6. The A's owners want to move the team to San Jose, but the Giants are trying to block the relocation plan because a decades-old agreement grants them territorial rights to the city. The orange and black certainly have San Jose's heart, if nothing else -- 86 percent of residents chose the Giants.

1. Unlike the A's, the Raiders are the chosen team in their hometown -- 57 percent of Oakland residents chose the silver and black. The Raiders won eight of the Bay Area's 162 towns, half of those in Alameda County, where they play.

2. Knightsen was one of three Bay Area towns where not a single resident liked either the Raiders or the A's.

3. The Raiders have a significantly bigger toehold on their rival's turf than the A's do -- 24 percent of San Francisco residents prefer the Raiders, compared with a piddling 9 percent A's loyalty.

4. The 49ers don't need to worry about competing for fans' affections in Santa Clara, the home of their new stadium starting next year. Seventy-two percent of residents there picked the Niners over the Raiders.

5. Though the Raiders can't make a claim to owning any Bay Area county, their levels of support in Alameda and Contra Costa counties indicate a true rivalry for fans' affections. In Richmond, the split is exactly 50-50.

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