I've never read Montesquieu but on cursory examination, it does indeed appear to mimic Machiavelli quite well.
However, Machiavelli dealt more with manipulation of the mob than suppression, and he also had no real preference for despotic leadership. His articles and works later than The Prince apply equally as well to a democratic state as they do to a despotic one.
This makes good sense, considering the preference in Italy at that time for the model of Republican Rome.