While the total number of voters who vote by mail is relatively small overall, it has increased steadily over the last six presidential elections, according to data compiled by Pew Research Center. In 1996, 7.8% of voters cast a ballot by mail, in 2000 it was 10.1%, 12.9% in 2004, 16.4% in 2008, 18.5% in 2012, and 20.9% in 2016.
States with plans to expand vote-by-mail in 2020 have different types of mail-in ballot rules and emergency exceptions due to COVID-19. However, vote-by-mail has subtly increased in these states as well.
There are five states where all ballots will be by mail-in ballots. In 1996, 26.6% of voters in these states voted by mail compared to 87.6% in 2016. In 29 states and the District of Columbia where there is no-excuse vote by mail, only 8.2% of voters cast a mail ballot in 1996, compared to 21.4% in 2016. In eleven states where an excuse is needed to vote by mail but where eligibility has been expanded due to COVID-19, only 3.5% of voters cast a mail ballot in 1996 compared to 4.6% in 2016 – just a one percentage point increase. And in five states where an excuse is needed to vote by mail that have not yet put in place expansions because of COVID-19, 3.5% of voters voted by mail in 1996, compared to 5.8% in 2016.
States and the Democrats have pushed for all-mail-ballot elections for some time. President Donald Trump and others have raised concerns about the practice in 2020. Vote-by-mail will undoubtedly increase in 2020, as seen in states like Georgia and New York that held their primaries over this month. Turnout may not increase at the rate that many predict, however, if historic trends are any guide. That said, smart campaigns will prepare their GOTV efforts accordingly and account for voters making their decision in the weeks before in-person voting on Election Day.