OK, I did the research. Richmond County, NY (Staten Island) was one of only 9 counties to have voted for McCain in 2008 and for Obama in 2012:
Chaffee County, CO
Early County, GA
Woodbury County, IA
Franklin County, KY
Somerset County, MD
Warren County, MS
Richmond County, NY
Nash County, NC
Darlington County, SC
Of those 9 counties, 3 previously had voted for Gore in 2000 and Bush in 2004:
Franklin County, KY
Somerset County, MD
Richmond County, NY
Somerset County (in the southern part of MD’s Eastern Shore) was most similar to Richmond County in that it had voted for Bush in 2004 by a wide margin and narrowly for the other three; Franklin County (Frankfort) voted narrowly for the winning candidate all four times.
I knew it was a very small number of counties that switched to Obama.
Gore/Bush/McCain/Obama is such a queer combo I’m surprised there are even 3 of them.
Somerset MD and Franklin (Frankfort) Kentucky can be explained by even bigger Black turnout than 2008 and Staten Island by the hurricane. It would does not surprise me turnout was so low there, I hear that place was Katrinaed but good.