Writing in The New York Times to summarize their recent paper, scholars Charlotte Hill and Jacob Grumbach have looked at the impact of same-day voter registration laws, which let voters register at the same time they cast a ballot, and have concluded that the policy is one of the most effective ways to improve voter turnout.
The study relied on the Census Bureau's Current Population Survey Voter Supplement, which is a large-scale statistical sample of the country. The researchers compared voters in states that do allow same-day registration with demographically similar Americans living in states that do not.
The analysis shows that same-day registration laws would increase turnout in a presidential electorate, a result consistent with those of other studies, and it specifically finds the largest increase among young voters. The authors lay out the ways in which registration laws disproportionately burden younger people, since they are much more likely to change addresses and thus have to reregister each time.
In particular, the study estimates that presidential election turnout among those ages 18 to 24, typically the group with the lowest turnout, could surge from 30% to as much as 40% with same-day registration. While older voters would be more likely to turn out, too, the share of the electorate that is over 35 years old could fall by more than 2%. Consequently, the authors conclude that turnout would become more demographically reflective of the citizenry along the lines of age, race, and income, in turn making it more Democratic.
Looking specifically at Michigan in 2016, which Donald Trump won by just shy of 11,000 votes, Hill and Grumbach conclude that same-day registration would have flipped the state to Hillary Clinton by producing a net gain of 90,000 Democratic votes. Michigan voters enacted same-day registration by ballot initiative in 2018, so the researchers will be able to re-evaluate their analysis after the 2020 elections to review its impact there.
While expanding access to voting often becomes a partisan battle against GOP opposition, some Republicans have been open to same-day registration. Utah Republicans passed the policy in 2018, and it remains the law in other red states, such as Idaho. Deeply conservative North Dakota, meanwhile, is the lone state in the country that doesn't even require registration: Citizens simply have to prove their identity and swear that they're eligible. Nevertheless, voter impersonation fraud is still practically nonexistent.
Still, most of the recent action to expand same-day registration has come from Democrats. Just this year, states with Democratic-run governments, such as Nevada and New Mexico, both passed same-day registration into law. New York Democrats also passed the policy but will have to pass it again in 2021 and win a 2022 referendum to amend their constitution. Similarly, Maryland Democrats also implemented a voter-approved same-day registration law.
A number of states where Democrats hold power have yet to pass same-day registration. As shown on the map at the top of this post (see here for a larger version), this includes states where they have full control of government—specifically Delaware, New Jersey, Oregon, and Rhode Island—and also Massachusetts, where they have veto-proof majorities with a Republican governor (who, in any event, previously signed automatic registration into law). Furthermore, several other states could follow Michigan's lead and use ballot initiatives to circumvent GOP hostility, including Arizona, Florida, Missouri, and Ohio.
Voter registration is one of the most formidable barriers to voter turnout, and it's that way by design: Registration laws arose in the mid-1800s largely as a way for the nation's Anglo-Saxon Protestant elite to disenfranchise America's burgeoning working class, including waves of Catholic immigrants from Ireland and elsewhere. Such laws were later a staple of Jim Crow efforts to bar African Americans from voting by making it much more difficult for black voters to register than for white voters.
Making registration both automatic and as easy as possible, which is the norm in many other industrialized democracies, will help both undo this legacy and improve turnout. With Senate Republicans blocking House Democrats' efforts to pass national same-day registration, states now have the chief role to play in implementing this key reform.