Book sales aren't actually the point.
The primary objective is to get a five or six-figure advance from some uber-lib publisher (who probably turns around and writes it off as a political donation), then flounce from one MSM primping station to another getting thy brow and ego stroked while reviewing offers to go become a stone waste of oxygen on some fool's College Faculty.
Timmy G probably will wind up "teaching" economics at Harvard by the end of next year.
...provided somebody doesn't decide he REALLY should be sent to a nice SuperMax berth for his great thefts and general malfeasance.
Unbelievable what the political elite get away with.