As far as I can tell, last time it happenned in a Presidential race was 1996 in SC
As I said upthread, the last time actually was quite recently- Alaska 2012. Of course, "counties" is a bit of a misnomer in Alaska, but Obama won the majority of county-equivalents- boroughs and unincorporated census areas.
Although not if you just count the actual
counties boroughs and ignore the Census Bureau's statistical divisions of the Unincorporated Borough.
Also, whoever made that wiki map seems to have used my data and translated them to media color scheme. Goodgood. Very good. Also seems to be making other election maps on wikipedia. Anybody here know who "inqvisitor" is?