Assuming we don't go back in time and change history to produce President Hillary Clinton (2009-2017), either Biden or Sanders would have won. Biden would have prevented the hemorrhaging of previously-reliable WWC voters in pivotal states and Sanders would have completely negated Trump's appeal as an "outsider" to leaning voters across a wide variety of demographics. Either way, it would have been enough to keep PA/WI/MI in the Democratic column.
Sanders would have lost NV though , and maybe even VA
Maybe the former (very skeptical)...but against Trump, definitely not the latter. Throw in ME-2 and Sanders is still at 273.