Huh this is strange, Whats with 20% of democrats voting for ford while carter only got 10% of republicans?
http://en.wikipedia.org/wiki/United_States_presidential_election,_1976#Voter_demographics
Carter should of been the archtype democrat who could bring back the white conservative democrats back to the party. White evangelical southerner who grew up humble and had a folksy peanut farmer image. What explains why there were double of cross-party votes in favor of ford than the reverse?
If carter gained just 10% of democrats that went to ford he would of got a 400+ EV landslide
Everyone and their grandmother were Democrats back then. Registered Republicans made up only a little over a quarter of the population. The potential for Democratic crossovers to Ford therefore would naturally be larger than the opposite scenario. Those stats you are looking at for people who identify as "Democrats", so I imagine that for 1972 the number of Democrats voting for Nixon would be somewhere in the mid thirties if not higher.
Just my five cents.