The confederate guerrillas in Kansas and Missouri under Quantrill, Anderson and Clement were nothing if not well-armed and committed. In the end, though, they were hunted down and killed, even years after the war (when they turned into James Gang).
But Quantrill, Anderson, and Clement were relatively small scale in the grand scheme of things. (You could include Mosby’s Raiders in that “small scale” description). I was talking about a large scale generalized guerilla war WITHOUT a conventional component. Imagine all the fighting men raised for the Confederate Armies instead engaged in hit and run type operations and returning back to blend in with the population. It might not have ultimately had any more success than the conventional operation did, but it certainly makes you wonder if such a large scale guerilla operation might not have given the South a better shot.
The simple truth is that the South never had ANY chance of winning a conventional war against the North. Their only chance in the actual event was to create enough political discord in the North to cause the North to abandon the war effort. Guerilla war may well have given the South a better chance for a military victory. Obviously, we’ll never know, but I think it’s an interesting idea.