lets assume that FDR doesn’t die in 45, and won’t die until at least 53 for irrelevant reasons. WWII ends in the same way. What peace deal does FDR scrounge up? Who does he run with in 48, does he win? What is his fifth term like? The rest of his fourth?
A school of historians believe that FDR would have run in 48 for the same reasons he ran in 44, he knew the war would be over soon but still felt he had stuff to do.