Though not post-1980 ...
I heard on NPR ("TOTN") the other week that, had the electoral votes in the 1976 election been distributed according to the Congressional District Method (distributed based on the popular vote winner within each of the state’s congressional districts; the statewide popular vote winner receives two additional electoral votes - as is done in Nebraska & Maine, and as Pennsylvania is considering doing in 2012) the Electoral Vote would have ended up as a 269-269 tie.