I have no idea exactly how that works. Anyone playing that game is likely wading into waters that are over their head, considering how much power the party leaders have consolidated.
I've mentioned my admiration for Heath Shuler before. He was concerned about the hard left turn the Dem party was taking so he challenged Nancy for Speaker. He didn't run for reelection afterwards. Bart Stupak suffered the same date after trying and failing to stop the taxpayer funding of abortion in the ACA. Anyone who tries to thwart Chuck or Nancy better already be planning a career change. It's a reason for concern with Manchin. He may want to stand against the craziness that his party has embraced, but he also genuinely cares about his state. That gives leadership a lot of leverage.