(Georges Gobet/AFP/Getty Images)

Fifty years after the passage of the Voting Rights Act, election laws are still in the news.

Much of the recent attention has gone to court battles over voter ID laws. But other barriers to voting remain. Although some states allow voters to register right up to Election Day, others require registration as much as one month beforehand. In the typical state in 2012, registration was closed for three weeks before the election.

Some scholars argue that requiring early registration hurts voter mobilization in the final days of the campaign, when interest in the election is most intense. But skeptics counter that most of the people who fail to register in time have little real interest in voting.

Our new research shows that there is a lot of last-minute interest. We estimate that keeping registration open through Election Day in 2012 would have allowed an additional 3 million to 4 million Americans to register and vote.

We used the number of Google searches for “register to vote” in the weeks leading up to the 2012 election to measure late interest in registering. These search terms were entered millions of times, and much of the activity fell at the very end of the campaign period.

To estimate the relationship between searching online, and actually registering, we turned to state records of registered voters. The data confirm that, in the period leading up to voter registration deadlines, the daily number of Google searches in each state was closely related to the daily number who registered. If the same pattern had been allowed to continue up to Election Day, millions more Americans would have registered in time to vote.

Turnout is higher in states that allow voters to register on Election Day. Despite fears over administrative difficulties, surveys show that polling place wait times are actually shorter in states with election-day registration than in the rest of the country. Fears of voter fraud are sometimes cited as a reason against allowing election-day registration. But all of the research shows that voter fraud is extremely rare.

In recent years, several additional states, including California and Illinois, have moved to allow election-day registration. But others have shifted in the opposite direction: Florida and Ohio have shortened the early voting period for absentees. North Carolina recently put an end to absentee registration and voting on the Sunday before Election Day. This came after African American churches organized buses to take “souls to the polls” after attending service. Legislators in Maine and Montana recently passed bills to repeal election-day registration, but were blocked by the governor or by referendum.

Our research suggests that early registration requirements have real consequences. New technologies make online registration, or same-day registration and voting, much easier to administer — and, if Google searches are any indicator, these reforms would help more people vote.

Alex Street is an assistant professor of political science at Carroll College.