I’ve read that it is a strong possibility that LBJ bowed out of the rat primary in ‘68 because he thought he would ultimately be named the nominee at the rat convention. Humphrey snuck in and that was that. If Ubama bows out, it will likely be Hillary. And the Clintons know it. Man, are those two playing this right. Hillary is keeping a high profile from other parts of the world while the economy here at home collapses at Ubama’s feet.
I think LBJ actually had enough health issues and he figured he wouldn’t survive another four-year term.