(or any other religious following large enough to be a player)

But if Schumer and Jeffries are not doing that, then other possible politicians could fill the gap by promising that if supported (support seen in both issue and election polls) they will press for leadership roles. This could put pressure on Schumer and Jeffries if they want to keep their spots.

It isn't rocket science so much as willingness to fuel a known "rocket engine" in the right way.