Both of his parents were dead in a car accident when he was little, so he probably received some grant/loans from the govt. Gloria also worked and from memory I'm sure she mentioned she helped him.
that kind of burden to repay his wife and the govt. and Archie would not be easy on anyone. Remember, he was supposed to be in his early 20s. Also during the episode Mike Comes Into Money he did work briefly at a gas station to raise the $200 he donated to the McGovern campaign (money Mike inherited from his Uncle Alex) over Archie's objections in order to help repay some of his room and board
