How the Dem Party rigged delegate counts

538 notes that the DNC has decided to reinterpret a rule for 2020 that "any candidate who is no longer running loses the statewide delegates they have won and those delegates are then reallocated to candidates still in the race." Previously this was not how they applied the rule. 538 goes on to discuss how this will cause Sanders to lose up to a third of his delegates going into the convention. Delegate count is important because a candidate needs at least 25% of them to get representatives on committees. Also, the higher the delegate count the more leverage one has to influence policy and the platform. So really, WTF is up with the Party?