Here is a histogram of the state scores, which are pretty much as you would expect.
Here is a plot of the election scores by year:
Of course, the basic trend is that the South has moved towards the Republicans over the century. The more interesting thing is that the movement was pretty much complete by 1972. The South moved back a bit towards the Democrats in 1976 and 1980 (when Jimmy Carter was running), but apart from that there's been little variation since 1972. I suspect that Southern whites have moved a bit more towards the Republicans during that time, but that's been offset by increased turnout among blacks.