I was playing with the electoral map, below, and have a sure-fire strategy for the Dems. If the Dems can win Florida, which they almost did last time and in which Trump is currently behind, and one of the three mid-western states that Trump barely won last time, Trump is out. So why don't they pick the candidate that is most popular in Florida, and that Wisconsin and Pennsylvania don't hate and go for it? Currently that would be Biden.
https://www.270towin.com/maps/2016-actual-electoral-map
From NYTimes
WASHINGTON — Democrats in the country’s most pivotal general election battlegrounds prefer a moderate presidential nominee who would seek common ground with Republicans rather than pursue an ambitious, progressive agenda, according to a New York Times/Siena College poll of primary voters across six states.
As the Democratic candidates intensify their argument over how best to defeat President Trump, their core voters in Michigan, Wisconsin, Pennsylvania, North Carolina, Arizona and Florida are counseling them to pursue a political middle ground.
A majority of those surveyed said they wanted a Democratic nominee who is more moderate than most Democrats, and they overwhelmingly preferred one who would bridge the partisan divide in Washington.