What if FDR, while of course still criticizing Mussolini's decision to enter the war, does so more "diplomatically" and does not use that phrase? Many Italian-Americans resented it, not necessarily because of sympathy with Mussolini--though there was some of that--but because they saw it as playing on the stereotype of the Italian banditto.
My guess is that it probably did affect the electoral vote of one state--Michigan--given the narrowness of Willkie's victory in the state and the large size of the Italian-American community in Detroit. (Of course given the size of FDR's nationwide victory, Michigan's nineteen electoral votes were hardly necessary for him.) https://en.wikipedia.org/…/United_States_presidential_elect…