Will the Democratic Party collapse if they don't embrace Bernieism?

[The Undefeatable Debbie Stabenow]

In terms of winning elections, there is no one-size-fits-all answer to the question of whether to run more progressive candidates or run more moderate candidates. It all comes down to local conditions when it comes to district-wide or state-wide races. In the special election in GA-06, for instance; Bernie-esque economic populism would not have worked, considering how affluent and traditionally conservative the district as a whole is.

There are also certain states where "establishment" politicians with high name recognition in their state have a strong network among each other and you want to tailor to winning local endorsements from these high-profile figures, who are typically moderate. Virginia is maybe the most extreme example of this, where the recent primaries for the gubernatorial race really exemplified the power of more local endorsements. Northam, the slightly more moderate candidate, was endorsed by Sen. Kaine/Warner and Gov. McAuliffe (not to mention every other Democrat in Virginia's legislature), while Periello, the slightly more progressive candidate, was endorsed by big-name out-of-state figures, like Sen. Sanders/Warren. Guess who won? Northam, by a decent margin.

I would also argue that Clinton's loss in 2016 was hardly an indication of a failure to create popular policy. Instead, I think it was much more of an indication that Democrats need to work on their optics game, and that part of the loss is just attributed to dislike of Clinton specifically. I think another Democrat running on the exact same platform would've likely won the election.