Of the nation’s 435 congressional districts, none favored Barack Obama more than New York’s 15th Congressional District. This seat supported the president by a extraordinary 97-3 margin, and interestingly, Obama’s second-best district in the country also happens to be right next door (New York’s 13th, which backed him 95-5).

The 15th covers a little more than half of the Bronx and includes two of the borough’s most famous landmarks: Yankee Stadium and the Bronx Zoo. This area also includes the public housing complex where Supreme Court Justice Sonia Sotomayor grew up; in 2010, the building was renamed the Sotomayor Houses.

The district has the lowest median household income of any congressional district in the country at $25,801. Sixty-five percent of the residents here Hispanic, while 29 percent are black and just 3 percent are white. This area has long been the center of New York’s Puerto Rican population, though today, Dominicans make up a plurality of the district’s Latinos. However, in part because Puerto Ricans are automatically granted the right to vote if they move to the mainland, Puerto Rican office-holders still dominate local politics.

Among them is Democratic Rep. José E. Serrano, who has represented NY-15 since winning a 1990 special election. Serrano had served in the state Assembly when this district opened up, following Rep. Robert Garcia resignation after he was convicted of corruption. (Garcia served three months in jail, but his conviction was later reversed.) Under New York law, no primary was held: Instead, the county Democratic Party selected a nominee, and they chose Serrano. He easily won the general election that year, and he’s never faced serious opposition in either the primary or the general since.