Sixty percent of voters — nearly 70 million people — are projected to vote by mail nationwide during the coronavirus pandemic. Those who study absentee rejection rates estimate that 1 percent to 2 percent of those votes — potentially more than 1 million — won't count, which could make a difference in battleground states.
"The vote-by-mail ballot rejections are going to be the hanging chads of 2000," said Daniel Smith, a professor of political science at the University of Florida.
The risk of ballot rejection varies by demographics and geography. The rate of rejection tends to be higher for Black, Hispanic, female and younger voters, as well as for people who don't usually vote by mail.
Experts say it also tends to be higher in states that don't normally have a lot of absentee ballots — a category that includes the battleground states of Georgia, Nevada, North Carolina, Pennsylvania and Wisconsin. All five had less than 10 percent of turnout by mail in 2016, and they will see huge increases in mail votes this fall.
The problem, experts say, is that experience matters when it comes to counting mail-in ballots. And while tight vote margins are nothing new for purple states, many have never experienced an election in which such a high percentage of votes will arrive by mail. Amid round-the-clock efforts by election officials to expand access to mail ballots, rejection rates in past elections raise concerns that in some tightly contested states, the number of rejected ballots could be larger than the winning candidate's margin of victory.
Donald Trump's surprise 2016 victory was the result of razor-thin victories in three states — Wisconsin, Pennsylvania and Michigan. In two of those states, the numbers of rejected mail ballots from this year's primary elections were bigger than his margins of victory four years ago.
In its statewide primary in August, Michigan counted about 1.6 million absentee ballots, with over 13,500 of them rejected. If the tally of absentee ballots roughly doubles in November, as expected, the number of lost votes will likely be greater than Trump's 10,704-vote margin of victory in 2016.
In Wisconsin's April primary, over 23,000 absentee ballots were rejected. In 2016, Trump won Wisconsin by 22,748 votes.
In Pennsylvania, which Trump won four years ago by 44,292 votes, nearly 20,000 ballots were rejected in this year's primary as about 1.5 million people voted by absentee or mail ballots. An estimated 3 million people are expected to vote by mail in the general election.
'There are going to be mistakes made'
More than 34 million absentee votes have been cast already, according to NBC News Decision Desk/Target Smart.
In all but five states this election cycle, any voter is eligible to receive an absentee ballot, largely because of changes made in response to the Covid-19 pandemic.
As a result, some battleground states have seen seismic shifts in the way people vote. Some are expecting a tenfold or more increase in mail ballots as people decide that they don't want to go to polling places during the pandemic.
"When you're in a scenario like we are in Michigan ... where so many citizens are going to be voting by mail for the first time, there are going to be mistakes made," Michigan Secretary of State Jocelyn Benson said last month, noting that absentee voters don't get immediate indications as to whether their votes are counted. "That will lead to potential challenges, in my view, or difficulties in making sure that every valid vote is counted."
To meet this need, election officials have mobilized over the last seven months to hire more staff, redesign ballots and envelopes, invest in new technology, educate voters and loosen the rules about when ballots are disqualified.
In many states, primary elections in the spring and summer served as learning experiences for how to handle unprecedented rates of absentee voting. About 2 percent of absentee ballots were rejected during the primaries, based on data from 25 states, according to Michael McDonald, a professor of political science at the University of Florida.
Rejections usually occur for one of two reasons: Voters make mistakes while filling out ballots, or ballots arrive too late to be counted. In Georgia's June 9 primary, for example, nearly 1.5 million people successfully voted by mail, but over 9,000 ballots were returned late, and nearly 3,000 had invalid or missing signatures.
In North Carolina, where the presidential candidates are polling neck and neck, the statewide primary didn't provide officials or voters with any practice for the general election. Voting proceeded in person as in past years, because the primary occurred March 3, the day of the state's first reported Covid-19 case. Just 29,396 absentee ballots were submitted, and of those, more than 2,600 — almost 9 percent— were rejected.
North Carolina is bracing for an expected 1.5 million ballots cast by mail in the general election. While other states, like Wisconsin and Pennsylvania, have to wait until Election Day to begin processing — and rejecting — ballots, North Carolina began processing mail ballots in late September. So far, it is seeing about 3 percent of mail ballots not completed properly, said Karen Brinson Bell, executive director of the State Board of Elections.
"We consider [it] to be very good, given the fact that so many people have never used this voting method before," Bell said, noting that the state has unveiled numerous tools to make the process easier for voters, like online ballot tracking, online absentee request portals and a new, more user-friendly envelope design. Voters in North Carolina also now have the opportunity to correct, or "cure," ballots with certain disqualifying errors.
Disparities are already emerging among the ballots rejected so far in the general election, according to analyses by Smith, the University of Florida professor. In North Carolina, Black voters' ballots are being rejected at roughly three times the rate of white voters' ballots. In Florida, voter error, usually related to signature issues, has caused slightly less than 0.5 percent of ballots to be flagged for rejection overall, compared to 0.7 percent for Black and Hispanic voters and 1.2 percent for voters ages 18 to 23.
But officials say ballot rejection rates from state primaries aren't a perfect proxy for the general election, especially because so many primaries occurred within weeks or months of coronavirus-related shutdowns.
Wisconsin, where absentee voters were less than 5 percent of the turnout in the 2016 general election, had to deal with 60 percent of voters casting absentee ballots in its April primary, just a month after the coronavirus was declared a pandemic. The election was marked by confusion over absentee ballot deadlines, among other issues.
So far, the state has received over 1 million mailed ballots for the general election — more than seven times the total of mailed ballots in 2016. But election officials and experts point to state initiatives to improve the process for the general election, such as drop boxes, ballot tracking and behind-the-scenes changes to the administration of absentee ballot requests.
"This will be our fourth statewide election in 2020, so we've had quite a bit of practice," said Meagan Wolfe, who heads the Wisconsin Elections Commission. "It was more challenging at the beginning of the year, but we've grown quite a bit over the last few months."
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Still, both in Wisconsin and across the nation, absentee ballot rejections remain among the top election administration concerns for some experts. With just a week until the election, amid slowdowns at the U.S. Postal Service, experts and election officials recommend that voters take care to educate themselves about the process, "cure" ballots where possible, use in-person drop-off locations and track their ballots using online tools like those available in the key states of Michigan, Wisconsin, Pennsylvania and North Carolina.
"It's a sad situation when a ballot is rejected," said Barry Burden, a political science professor at the University of Wisconsin-Madison. "It's a real risk voters take. I don't think most voters would like their odds if they knew them."