It appears that the Democrats will hold the solid South (until President RFK), the Republicans the solid Northeast and West, and the Midwest (especially Ohio) very competitive.
The TL featuring those infoboxes starts with the POD of Teddy Roosevelt running again in 1908, which butterflies into the progressive wing of the GOP becoming much stronger than OTL. By the end of ALT WWII, the democrats are dominated by the southern segregationist wing and most conservative republicans defect to join them, making the democrats the conservative party with the GOP - after merging with the short-lived progressive party - the left-leaning party.
Hence RFK running as a republican. The dems hold their own through the early 60's, but as the civil rights movement gains momentum, the party realizes it has to change and A.B. "Happy" Chandler is nominated, running as a new breed of post-civil rights democrat in the mold of an OTL Jimmy Carter.
Obviously, the dems remain rooted in the south, as you can see by the nominations of John Connally and Sam Nunn in the 80's. I had some vague ideas of a Hillary Rodham (R) vs. Bill Clinton (D) election in 1996, given the two never met/married in this TL.