What may have happened in world war 2 if D Day had not taken place?

Nazi Germany would have had a great place to start invading Britain, by going across the channel. The war may have went on longer if we hadnt made such a blow against Germany at Normandy.

Presuming that the cross-channel invasion of Normandy did not occur, the forces built up for that effort would have gone to one of four likely places:

1. Reinforce the landings and fighting in Italy
2. Strengthen Operation Dragoon, the Allied landings in southern France in August 1944.
3. Equipment would have been shipped to the Soviet Union, to further increase the major Soviet Summer Offensive of 1944.
4. Men (and some material) would have been shipped back over to the Pacific Theater, likely to speed the invasion of the Philippines.

The primary consequence of a failure of D-Day (whether it happened and failed, or simply couldn't be initiated at all) is that the Western Allies would almost certainly have been bogged down in South-Central France and Northern Italy when the Soviet Red Army crushed the remains of the German Eastern Armies in central Germany, likely in mid-1945. As a consequence, most of Europe would have been liberated by Communist forces, and thus, there is a very high likelihood that most of continental Europe would have fallen under direct Communist influence and have had a Communist government. That is, there would have been a United Communist Germany, and a Communist Denmark, Belgium, The Netherlands, Austria, and possibly even France and Norway.