The most effective way to get those people to vote is to not have Hillary Clinton as your candidate.
Again, what makes you think that the people didn't stay because they sure didn't want to vote for Clinton?
(Disclaimer :I am not an US citizen, I identify with Bernie)
I would have never voted for Clinton, even if you paid me.
I only bother voting if there is a referendum or local politician I care about. Neither was true in this election. Living in Maryland I already knew Clinton would carry the state. So why go vote?
I bet there are people like that in deeply red states who feel the same. I bet voter turnout would be higher all around under a Popular vote scenario.
Voter turnout was still low in swing states are well, so I could be wrong. But I think at times people realize their vote is sort of pointless.
I think it is helpful in these situations to extend your thinking to everyone else and see if you like the result:
1) My candidate has a big lead in my state so I won't bother to vote. 2) My thinking in 1) is rational and therefore lots of other people will think and behave the same way.
vs.
1) My candidate will only win if their supporters vote for them, so I will vote. 2) My thinking in 1) is rational and therefore lots of other people will think and behave the same way.
So which behavior will most likely lead to your desired outcome?
I don't see how this is helpful. The calculus is obviously different between your state being carried 60/35 vs a 50/50 battleground.