And it’s worth emphasizing just how rare it is to see this level of consensus that a politician should resign. American politics have seen many scandals in recent years (it’s amazing some of the ones even a political reporter like myself can forget). And often, there are no polls testing voters’ attitudes about a given episode — either because nobody bothers to ask, or because the politician resigns before the situation festers long enough. But among the scandals we could find polling on, San...