This explainer was last updated on February 9, 2022.
Supporters of same-day registration argue that EDR boosts turnout and increases access to the ballot for members of disadvantaged groups who would otherwise be unlikely to vote. Opponents suggest that the relationship between EDR and turnout is unclear and point out that allowing same-day registration places an extra burden on local election officials. Opponents have also argued that EDR encourages turnout among people who are not well informed about the election and may lead to voter fraud by giving election officials less time to verify registration information.
EDR is a hotly contested and highly partisan issue. Across U.S. states, Republicans and Democrats alike have accused state legislatures of strategically implementing EDR to benefit the opposing party. To address the claims made by both proponents and opponents of EDR, researchers have been studying its effects on turnout, the demographic composition of the electorate, partisan competition, and the supposed increased administrative burden on election officials.
Current EDR Registration Requirements
The fine points of same-day registration procedures vary from state to state. Some allow EDR during the early voting period as well as on Election Day, while others limit EDR either of the two. In all states that allow EDR, voters who register and vote on the same day must present proof of residency at the time of registration. This requirement can be satisfied with a driver’s license or a state-issued ID card in all states, though some let voters submit utility bills and other documents displaying their address. Voters who use EDR must also present identification at the time of registration or shortly thereafter. Some states that allow EDR require a photo ID, while others do not. The National Conference of State Legislatures provides a table of state-by-state identification and proof of residency requirements under EDR.
Recent Legal Controversy Surrounding Same-Day Registration
For the People Act of 2021
The signature piece of legislation of the newly installed Democratic leadership in the 117th Congress was the For the People Act 2021, which was given the symbolic numbers of HR1 and S1 in the two chambers.
The 886-page bill contained a large number of provisions ranging across election administration, voting rights, and campaign finance. One provision would require any state that has a registration requirement to allow for same-day voter registration for all federal elections starting in November 2022. Unsurprisingly, this expansion of EDR has prompted contentious debate between Democrats (who are mostly in favor of the bill) and Republicans (who are mostly opposed). Though it passed through the House in March 2021, pundits believe the bill is unlikely to find acceptance in the Senate, where even some Democrats are reluctant to endorse its sweeping changes. As of the end of 2021, the bill had not passed the Senate.
In April 2021, Montana became the first state to eliminate EDR, when Governor Greg Gianforte signed H.B. 176 into law. This was after Montana voters had rejected a ballot measure six years before to end same-day registration. Numerous lawsuits have been filed in state courts by groups such as the Montana Democratic Party, Native voting rights organizations, and the ACLU.
In October 2016, the 7th U.S. Circuit Court of Appeals reinstated the state’s same-day registration law after it was blocked by a lower court. The lower court had ruled the state’s Election Day registration law unconstitutional because it required counties with 100,000 or more residents to provide voters with an EDR option at polling places. Less populous counties were not subject to this requirement. Opponents of the EDR law argued that it would provide a boost in turnout to largely Democratic, urban areas without doing the same for Republican-leaning rural areas.
Academic Research on Election Day Registration
The academic debate over EDR has focused on three broad questions. Researchers have tried to determine whether EDR has any effect on turnout. Scholars have also studied the extent to which EDR encourages voters from traditionally underrepresented groups to turn out or alters the partisan balance of elections.
Many political scientists have argued that EDR increases turnout. The theory underscoring this argument holds that registration requirements impose significant costs onto voters. In order to vote in an election, voters must: (1) learn the deadlines and procedures concerning registration (2) appear or mail-in documents prior to election day, and (3) appear again or submit separate documents to cast their ballots. By eliminating the first two steps, EDR makes it easier for voters to cast ballots (Wolfinger and Rosenstone 1980). Scholars have tried to test this theory using data from states that allow EDR, and many have concluded that EDR generally has a positive effect on turnout. While the size of this effect varies by study, scholars have generally reported three to six percent average gains in turnout in EDR states (Brians and Grofman 2001; Knack 2001; Alvarez, Ansolabehere, and Wilson 2002; Burden and Neiheisel 2012; Leighley and Nagler 2014). Researchers have pointed out that both registration and turnout were higher on average in EDR states than in non-EDR states (see Alvarez, Ansolabehere, and Wilson 2002).
Some studies have disputed the conclusion that EDR increases turnout. Researchers who have taken this position have pointed out that earlier studies tended to compare turnout in states with EDR to states without EDR. However, because turnout varies between states for reasons other than EDR, research designs that focus on changes within a state are more appropriate. When scholars have looked at changes in turnout within states, comparing turnout before and after EDR, the effect of EDR appears much smaller (Keele and Minozzi 2013).
Some scholarly research has found that EDR can change the composition of the electorate by making it easier for voters who have a difficult time meeting registration deadlines. A report of the Caltech/MIT Voting Technology Project found that EDR benefits voters who are younger, nonwhite, poorer, and less likely to have stable addresses (Alvarez, Ansolabehere, and Wilson 2002). Using Current Population Study data from several states, Craig Leonard Brians and Bernard Grofman find that EDR benefits low and middle-income voters most (Brians and Grofman 2001).
Research on the relationship between EDR and partisan competition is mixed. Scholars have noted that no aggregate evidence exists for an electoral benefit to either party. States which implemented EDR between 1980 and 1996 were about 5 percent more Democratic on average than non-EDR states, but states that passed EDR after 1996 were no different than other states in terms of partisan competition (Brians and Grofman 2001). In specific elections, however, there may be reason to believe that EDR does impact partisan competition. In their study of Wisconsin, for instance, Jacob Neiheisel and Barry Burden found that EDR correlated with a decrease in the Democratic share of the two-party presidential vote (Burden and Neiheisel 2012).
Finally, there is some disagreement over the administrative costs of implementing EDR. Surveys of local election administrators have revealed that, while election officials broadly supported EDR, more than half of them believed that implementing EDR would increase the administrative burden placed on them (Burden, et al. 2009). However, surveys of the post-implementation costs of EDR suggest that, in many cases, the monetary costs of implementation were relatively low. Election officials could not always identify the specific, additional costs associated with EDR (see 2012 Demos cost report).