Turnout patterns in Oregon

Oregon has been entirely vote-by-mail for nearly 10 years (even longer for non-federal elections). Voters can return their ballots in the mail, or they can drop them at elections offices and special ballot drop boxes located around the state. Over at Election Updates, EVIC’s Paul Gronke postulated that the particularly high number of late ballot returns in this election—36% in the last two days—could have been the cause of delayed counting in Oregon (particularly Multnomah County).

Ballot return trends over the past decade, however, don’t appear to support this theory. We know from past experience that many voters hold on to their ballots until election day; they have done so since the inception of vote-by-mail. The graph on the left shows the raw numbers of ballots returned in the last two days (this includes election day). The right graph shows the same as a percentage of total ballot returns. Clearly, the sheer volume of returns is not unprecedented—every general election, bar 2004, has had a high rate of late returns. I’ll see if I can track down some Multnomah-specific data to see if the county differed from the statewide pattern.