I don't think its possible with anything smaller than a ATR 42-300-600 series...
Ive run profitable with the ATR 42 which is a 50 seater,
The EMB-120 just doesn't work with how AWS works, mostly due to high staff costs... they say anything smaller than 50 seats and its a no goer...
the Q-400 is a GREAT plane for regional work in AWS... as is the ATR 72
I want one day, the ability to fly MITSUBISHI MU-2'S PROFITABLE (COUGH SAMI COUGH)
that last bit you might not get unless you saw my post :p but if you have any other questions let me know