At the risk of overgeneralizing, subject to more careful analysis, and feeling badly for maybe stereotyping:
Trump and Putin voters are blue collar, in declining industries, with little hope of long term improvement.
Trump and Putin voters are racial majorities and think they should stay that way.
Trump and Putin voters expect the state to take care of them — although they say the opposite.
Trump and Putin voters often rely for a sense of self on the superiority of their country and religion.
Trump and Putin voters are suffering declining life expectancy, with significantly increasing suicide, drug above, overdose, and medical problems.
Trump and Putin voters tend to project the causes of their problems onto outsiders, those that they see as vulnerable.
Trump and Putin voters seem unable to vote their economic interests, or at least their long term ones.
It is the last one that raises the question whether a long term Democratic strategy of trying to get back the Midwest makes any sense. The answer is that such a strategy only makes sense if enough of this population can go from seeing that the system is rigged to understanding who is rigging it and in what interest.