Hi Joe,
I will plead guilty that I made a mistake about the 50 Ten USV. Per the 1st Alabamacav.com among Union regiments that Northern Albamans joined ware the 12th Ten, 5th Ten Cav, 1st Middle Ten Cav. If 20% of White Tennesseans joined the Union thats a signifcant amount of manpower. If one includes the USCT regiments raised in Ten then arguably much more the 20% of male Tenesseans were loyal to the Union. An interesting question was why more Tenesseans joined the Union Army vs states such has Ga, Sc, and Miss?
Per the book "Linclon's Loyalists " by Richard Current approx 100k Southern White males joined the Union vs 850 to 900k that joined the CSA. It has to be concluded that of the major reasons that the CSA lost was because of the combination of White and Black Southeners fighting against the CSA gave the Union an overwhelming manpower advantage.

Politically it also gave the Union an advantage because in a cold cruel way one dead Unionist equals one less dead Union Soldier from a Northern state and Linclon in the summer of 1864 knew he would need every advantage it would take to beat McCllean since more casulties equal more Democratic votes.

By the same token there were thousands of White males from Mo,Ky, and Ml who fought with the CSA plus irregulars. I will of course stipulate that the CSA soldiers were tough and brave and did not have supplies in abundence has did the Union. Nonetheless having 20% plus of Southerns on the Union side was an obstacle thaat could not be overcome.

Leonard