Whether Democrats win the US Senate — and whether their senators are progressive — could be the difference between life and death for millions of people. A Democratic Senate filled with proponents of a Green New Deal and Medicare for All is one that at least offers the slim possibility of averting climate and health care cataclysms. A Republican Senate — or a Senate run by corporate Democrats — will almost certainly make the climate and health care emergencies far worse, likely resulting in mass casualties and suffering.

In this life-or-death battle, winnable Senate seats in Democratic-leaning states are everything. If we’re going to have any chance to survive the crises in front of us, these Senate seats cannot be lost to Republicans. They also cannot be bequeathed to Democratic corporatists who will defend the status quo and behave in reckless ways that jeopardize the party’s prospects of winning a general election.

But that is what Democratic leaders in Washington are trying to do here in Colorado — the state that could end up deciding control of the Senate. They are now spending big to buy the June 30 primary for a candidate who has shilled for fossil fuel companies, opposed Medicare for All, violated anti-corruption laws, vilified progressives, and engulfed himself in high-profile scandals that could lose a general election. And they are doing this even though there is another Democrat who is not only far more progressive, but arguably better positioned to defeat the Republican incumbent.