Starting a new thread to continue this discussion.
Here's the statistics regarding the U.S. vs Soviet Union efforts in World War II.
Casualties
Soviet Union: Anywhere from 8 to 10 million deaths.
United States: 137 000 dead.
Overall, half the casualties in the entire war were Russian.
Effects of Lend Lease
U.S. Lend Lease provided for critical deliveries of food and raw materials, but only accounted for 14% of the Red Air Force's planes and a fewer percentage of tanks. However, logistical support in the form of locomotives, rail cars, and trucks were indispensable to the Soviet war effort. So, not much in the way of arms, but very important in terms of logistics.
In terms of territory the front line ran a distance equal to that between Baltimore Maryland and Cheyenne Wyoming, so if you can imagine almost a third of the United States being churned into a battle zone where 20 million people were killed, and Chicago being battered and starved for 900 days, then you kind of get the picture.
Give the devil his due. The Red Army defeated the bulk of the German Army on the battlefield, and probably could have won the war even if D-Day never happened. They could not have won without our M-3's though.