[CaptainHaplo]

Ultimately - there are 3 reasons the russians would have lost.

The Bomb - more would have been made - and used - to force unacceptable infrastructure losses upon the russians.

Production Capability - the russians ultimately would have found their ability to wage war whittled away. The Allies - with its largest contributor the US - would have had no such problem. No russian attack could have been mounted against the production capability of the US - and the supply lines over the oceans were secure.

Civilian concerns - a wartime people - stretched thin via war - and suffering at home with the loss of industrial ability represent a HUGE threat to power in a communist system. It is said that the Czars never really understood the danger the people presented - and that is how communism and the bolsheviks truly found fertile soil. Those same people that lifted the bolsheviks to power had to be dealt with - and ultimately you can't send everyone to the gulag - because after a while - there is no one left. The same applies to any government of people - but in a system that purportes total equality among its governed - the danger is far greater when the disparity becomes too great, and the burden too great for the people.