poor smuck
a poor smuck is the guy who is basically a loser who is caught in a web of circumstances that seem to be beyond his power to change his life. Actually if he had the determination to stand up and pull himself out of his situation he would probably be a weak normal person. However he feels so beaten down he is afraid to stand up and make his choices.
A guy living with a dominering wife, kids and mother-in-law and stuck in a low paying job with a doctor's degree is a poor smuck.