Suppose that, due to the political chips falling differently in Kentucky during the volatile time of 1860-61, that Kentucky secedes and joins the Confederacy in April of 1861 along with the other "Upper South" states and thereafter supports the Confederate war effort with pretty much the same level of enthusiasm as North Carolina and Virginia.
Does this make little or no difference? Does it mean a somewhat more difficult or much more difficult war war for the Union, but eventually a victory? Does it mean a Confederate victory?