We usually have had less than 30% participation for the local Democratic primary in off years (Republican primary in off-years is not much better). The complete lack of civic-mindedness is why the only strategy that works at the general election is "vote for the lesser evil." Note: that only include 2 viable candidates, a third party will never win the Presidential election without elimination of the parties themselves or implementation of rank-choice voting by a majority of states to counteract the anti-democratic (that's small "d") bias of the Electoral College.