I am no Nazi sympathizer, but I think history does point to many Germans -- perhaps moreso the German high command than common soldier or civilian -- that thought Hitler was leading the country to ruin well before 1943/45.
If you believe Churchill's writings in "The Gathering Storm", the German military command was at odds with Hitler during his most triumphant conquests. They knew that their army could not attack Austria, Chechlozvakia, and Poland at the times that they did and keep the western allies at bay if they decided to march against Germany. Hitler, however, judged correctly that France and England were blinded by thoughts of peace and would not war with him. Even when war was finally declared after the invasion of Poland, the allies did nothing but wait for Germany to turn its military spear-point upon them (actions in Norway notwithstanding).
Churchill writes of many plots by the German military command to arrest Hitler during this time. None of these were carried out for various reasons, the foremost being the vindication of Hitler's brazen agressions by the Allies lack of a response at every turn. By the time things became difficult for Germany, they had conquered most of Europe and Hitler's prestige made him nearly inassailable.
Gordo