YES. My husband has done it numerous times. Make sure it is in a securely-shutting guitar case, and as you are boarding the plane, ask the attendant to check it as a carry-on. (We already had 1 bag of carry-on each, so we were afraid that the guitar would be over the carry-on limit – but our attendant checked it as carry-on, and explained that it would be stored with the luggage. So we got it right back each time we disembarked a plane, we just picked it up on the rack right outside the plane.) Of course, it will be stowed with the cargo.
Edit: Just read that you had a soft case. That should be alright, but if you are super-protective of your guitar, I would see if you could maybe borrow a hard, sturdy case from a friend to use on the flight.