Following the model of yesterday’s map of California, below is a map of how New York counties have voted in the Democratic primaries of 1980, 1984, and 1992. One big difference is that New York’s primary votes are highly concentrated in a small area; New York City has a much bigger footprint, electorally, than Los Angeles has in California. The percentages shown on the map refer to the share of the total votes in the 2004 Democratic presidential primary that came from each group of counties with similar voting patterns, and the dominant group includes all five boroughs of Manhattan, plus suburban Nassau, Westchester, Rockland, Orange, and Sullivan counties, as well as Rensselaer County on the Massachusetts border. Not surprisingly, this group supported the statewide winners of Ted Kennedy in 1980, Walter Mondale, in 1984, and Bill Clinton in 1992.

A subgroup of three boroughs — the Bronx, Brooklyn, and Manhattan — voted for Jesse Jackson in 1988, while the rest of metropolitan New York supported Michael Dukakis. Can Barack Obama take these boroughs against home state candidate Hillary Clinton? Perhaps, but they may not vote in unison: The Bronx, with its heavily Latino population, was the only county in the state to give an absolute majority to Bill Clinton over Paul Tsongas and Jerry Brown in 1992.

The second biggest grouping of counties is in dark green on our map, and it covers the cities of Buffalo and Rochester, along with the suburbs and small towns between them. Interestingly, it broke in the opposite direction from New York City in 1980, snubbing Ted Kennedy and sticking with Jimmy Carter. This coolness toward Obama’s most prominent endorser, along with Hillary Clinton’s close attention to upstate matters during her time in the US Senate, indicates that she should do very well here no matter what happens in NYC.