After Thursday night’s debate, this much, at least, is clear: The central issue of the 2020 Democratic presidential primary is corruption.

Not purity. Not electability. Not socialism or fiscal responsibility or any of the other buzzwords floating around the party discourse. Corruption.

The corruption question is simple: Will the richest people in America be permitted to put their fingers on the scales of our democracy ― including the inner workings of the Democratic Party?

For two candidates in the race, Sens. Elizabeth Warren (D-Mass.) and Bernie Sanders (I-Vt.), the answer to that question has been a consistent, resounding “no.” They don’t court big donors, don’t hold big-dollar fundraisers for them, and won’t even meet with them behind closed doors. If you want Warren’s attention, you can get in line for a selfie with everyone else. Sanders even scrutinizes his contributions and returns checks from people who are too rich.