National vote-by-mail standards needed to avoid election confusion

I’ve lived in two exclusive vote-by-mail states during my time as an eligible voter. My first ballot ever cast was via the mailbox in Oregon. There the ballots are due in the hands of election officials by 8 p.m. on election night to be counted. Now living in Washington, I’ve trained myself not to worry about election results until the Friday following election day due to the state’s postmark deadline eligibility for ballots.

I’ve often wondered how the country would react to the Washington experience of not knowing election results for days (if not weeks) until after the election. For better...