Have Joe Steele be Al Smith's VP. Because this is Turtledove, the rest stays mostly the same minus the superbomb development, which was way too exaggerated in TL-191 and in the Steele-TL takes longer to develop.
Steele would not let Texas go independent, or allow Dewey to win the Presidency in 1944, he stays in power until his death a decade later.
There is a much higher chance that we actually end up with a US that looks much more Soviet Union-y in TTL. Although Steele was adamantly anti-communist in his novel, it is likely he goes socialist in TTL due to TL-191 politics.