It is beyond strange that people think 1972 is a better predictor of 2020 than 2016

[Scurrilous]

6. I'll do Democratic Congressional & Senatorial Campaign Committees as a benchmark.

2018

The organization with the best endorsement record in Democratic primaries remains the Democratic Party itself. Candidates who are on the Democratic Congressional Campaign Committee’s Red to Blue List or endorsed by the Democratic Senatorial Campaign Committee7 had a win rate of 95 percent (37 wins out of 39 endorsements). In races where a party-endorsed candidate ran against a progressive-group-endorsed candidate (excluding any races where a candidate was endorsed by both sides), the party-endorsed candidate won 89 percent of the time.

In other words, the best predictor of primary success remains establishment support.

https://fivethirtyeight.com/features/the-establishment-is-beating-the-progressive-wing-in-democratic-primaries-so-far/

How candidates endorsed by selected people and groups have fared in open Democratic primaries for Senate, House and governor in 2018

Endorsed Win Percent

Joe Biden - 10 10 100%
Elizabeth Warren - 5 5 100
Democratic Party committees - 39 37 95
Emily’s List - 54 39 72
PCCC - 15 10 67
Indivisible - 46 30 65
VoteVets - 28 16 57
Bernie Sanders - 9 5 56
Working Families Party - 30 15 50
Gun Sense - 192 79 41
Justice Dems - 50 16 32
Our Revolution - 85 27 32