The country has had contentious elections before, 1800 leaps to mind, when two Founding Fathers went at it, or their minions did (they didn't campaign directly back then).
Adams and Jefferson became political enemies after this, until years later when they made up. But if we take most of the candidates in our history back when in terms of their basic honesty, decency, capacity, and good intentions, throw out political positions, my opinion is we had some solid choices more often than not. Few of them were flat incompetent, or schills, or greedy bastages, or whatever.
Obviously some were less then memorable, but most of them were decent enough folks. Our two choices during my lifetime have often not met that bar, in my view.
The last candidate I truly admired was Bill Bradley in 2000. I didn't agree with all of his positions at the time, but I did think he was more than competent, and honest, and capable, and decent, and wanted the best for the country. I have not felt that way since, and rarely before him in my lifetime.
