*("major" is obviously a subjective term depending on who's using it.)
Until this weekend, "Medicare for All or Bust" seemed to be the most critical litmus test for any major 2020 Democratic Presidential candidate. No fewer than sixteen Democratic Senators co-sponsored Bernie Sanders' S.1804 "Medicare for All" single payer bill in September 2017, including five of the six U.S. Senators currently running for the 2020 nomination: Sanders himself, Cory Booker, Kirsten Gillibrand, Kamala Harris and Elizabeth Warren (the only Senator running who didn't cosponsor the bill was Amy Klobuchar.)
Recently, however, there have been a few interesting developments along the "Where do the Dem candidates stand on healthcare policy" front:
Early concept art has revealed a very different look for Toy Story's dynamic duo, Woody and Buzz Lightyear.
Pixar's first feature started life as a full-length take on their short Tin Story, which saw a mechanical drummer attempting to navigate his way through a baby's playroom. The drummer was soon ditched for a more glamorously conceived "space toy" named Lunar Larry, later renamed Buzz Lightyear in honour of famed astronaut Edwin "Buzz" Aldrin.
The original concept pitched its drummer against an antagonistic ventriloquist's dummy, who gradually evolved into a pull-string cowboy doll named Woody, inspired by Western actor Woody Strode.
Yes, Woody was originally the bad guy; though his character didn't prove popular with his voice actor Tom Hanks, who reportedly shouted "This guy is a jerk!" while recording lines for the story reel.
UPDATE 4/16/19: Please note that this overview refers to the version of Medicare for America introduced in December 2018. There's a revised version of the bill being re-introduced in the near future which is expected to include several important changes. The only two which have been made public so far are: 1) Deductibles are expected to be eliminated altogether; and 2) the upper-end percent-of-income maximum premium is supposed to drop from 9.69% to an even 9.0%.
There's a half-dozen or more different healthcare policy overhaul bills which are being batted around by Congressional Democrats these days, ranging from the fairly modest ("lower the Medicare buy-in to age 50!") up through the full-blown, "pure" Single Payer bill being pushed by Bernie Sanders & other "Medicare for All" activists.