How The Democrats Will Lose in 2020

And there's always the possibility that the economy will tank: America has experienced an economic downturn at least once per decade for the past several decades, and our last serious downturn was in 2009.
With all of that said, Democrats can still find a way to blow this.
They could blow this in the same way they blew 2016: by picking a candidate based on intersectional concerns rather than capacity to unify Americans, and by slandering half the country.