What might have happened if Lincoln had replaced McClellan with Grant earlier in the war?

If Lincoln had replaced McClellan with Grant earlier in the war, the Union might have benefited from Grant's more aggressive and decisive leadership sooner. This could have potentially led to earlier victories in key battles, such as Antietam or Fredericksburg, which might have boosted Northern morale and strengthened support for the war effort. Additionally, an earlier implementation of Grant's strategies could have accelerated the depletion of Confederate resources and manpower, possibly shortening the war. However, it's also possible that the Union Army might have faced setbacks due to the challenges of warfare at that time, regardless of leadership changes.