Here is what Mencken had to say about the Dixiecrats (p. 94):
The result today [of the South's previous history of misdeeds] is that the Dixiecrat movement is getting a great deal less sober attention than it deserves. It looks, from across the Potomac and Ohio, like nothing more than a fresh pestilence of Longs, Bilbos, Tillmans, Bleases, Talmadges and Pappy O'Daniels. It is, in fact, nothing of the sort, whatever the excrescences that now burden it. It is fundamentally quite as serious in purpose, and quite as rational, as any other regional movement that has appeared in recent years, and some of its leaders are worthy of the highest respect. Certainly it would be absurd to dismiss such men as Governor J. Strom Thurmond, of South Carolina, and former Governor Dan Moody, of Texas, as windbags of the common sort. They are men of intelligence, and they are men of honor, and when they take to the bush it is safe to assume that they have a genuine grievance.
I can think of one more book that may interest you. I found at the Minneapolis Public Library a few years ago.
Read "Quixotic Crusade".
It's writen about Wallace and the Progressive Party' 1948 campaign. Quite fascinating but it has been out of print for a while. If you can find it somewhere, it is well worth the read.