Let's propose a few things: One, that in a move that shocked nobody more than the challenger himself, Ely was able to obtain the nomination of the Democratic Party and oust the incumbent President. The second, being that Huey Long was never assassinated in 1935, and is alive to actively campaign for the Union Party. Finally, that Floyd B. Olson never succumbed to an early death. So, without further ado...
Alfred E. Landon (R-KS)/Frank Knox (R-IL)
vs
Joseph B. Ely (D-MA)/Henry S. Breckinridge (D-NY)
vs
Floyd B. Olson (U-MN)/Upton Sinclair (U-CA)