1976 Presidential election: why was it so close?

[TDAS04]

The white vote was much more evenly distributed around the country than it is today in terms of who got what percentage in each state.  Here is an old thread of mine.  Shua made a map in which he estimated that Carter carried the white vote in only eight states.  Even if the white vote was fairly close nationally, it is still plausible that Ford carried it in the vast majority of states, and in the South overall.