Magoffin was solidly pro-Confederate and wanted the state to secede, the legislature was much more pro-union and wanted to stay Union, the eventual results was neutrality. Most of the state by area supported the Confederacy, but the population was concentrated along the Ohio river, and Louisville has the Falls of the Ohio which can provide an effective blockade for any shipping up river. Southern Illinois was also flirting with secession and a Confederate KY might make Cairo - Mt Vernon area tempted to leave. KY has signficiant industry, coal resources, manpower, tobacco, a north-south railroad, and notable coal resources. You can control the Ohio without putting troops in Indiana, Ohio, or Illinois if KY is frmy under your control though in this case I don't think the CSA would have rock-solid control in a war situation. At one point in 1862 KY was largely under Confederate domination and Bragg could easily have swung west from Lexington to take Louisville, leaving Cincinnati open and exposing Indianapolis to danger. Remember that a lot of Union manpower comes from states on the northern side of the river, and if Rebels are rampaging across the homestead what will those Union troops in the East do?
I'm not sure it would win them the war or even drag the war on, most of KY thinks of itself as a Southern state these days anyway so not sure that even taking the state has a dramatic outcome...
I'm not sure it would win them the war or even drag the war on, most of KY thinks of itself as a Southern state these days anyway so not sure that even taking the state has a dramatic outcome...