Roger Cohen has what has to be a parody of the genre in the NYT, but of course isn't, which is basically "why can't Democrats appeal to the people least likely to vote for them?"
In this case it is literally a 78-year-old lifelong Republican, former Republican politician, from New Jersey, who it seems has never voted for a Democrat in his life and of course voted for Trump. He might still vote for Trump! But only if Democrats go with... well... anybody they will nominate, because that's always how it works. I doubt he'd even vote for Democrat-for-President John Kasich.
One thing that should jump out is that this guy lives in New Jersey which means that his nonvote for Bernie Stalin isn't likely to matter much.
But generally this is "centrist" pundit thing which is that what Democrats should be is Republicans-without-the-gross-stuff. The shorthand for this is "economically conservative (no taxes for rich people and no nice things for anybody) and socially liberal." But they aren't really socially liberal, either. They think obvious explicit bigotry is offensive, but they're as suspicious of any attempts to correct structural and institutional racism (etc) even that committed by the state. Stop and frisk is sadly necessary, black people. "Rich ladies should be allowed to get abortions" feminism.
These are also the people that love to imagine liberals/lefties live in some imaginary hippie commune bubble. But to write a column like that without any awareness of how fucking absurd it is...