Rush Limbaugh was talking about this yesterday afternoon. These sorts of swings are unusual even if one could come up with rational reasons for some swing movements, minor.
POTUS got out the early vote and that panicked the DEMS everywhere but some more than others. Depends on discipline or fear of consequences of 1) losing the particular race and/ or 2) not meeting expectations of pol master(s).
It is cover. If she remains a prominent presidential "hopeful" then any indictments and the rest will be brushed off as attacks on an active political opponent. That status has shielded her for a v long time – next president, first woman president, just this close to winning. And on and on.
Her health may not permit a real run at it in 2020, anyway. But if she has poor health that becomes more cover against justice being served.
She will not go at a time of her own choosing. So even then expect political cover in death.