I spotted this article found by Dr Postman on the Ageod forum and thought I'd share it with you. It's a really good read about the campaign in the American South-West during the Civil War. If you play Civil War 2 it makes it obvious just how important supply considerations actually were.
http://www.civilwar.org/battlefields/glorietapass/glorieta-pass-history-articles/glorietaalberts.html
^Nice find.