Voting early enough was the key to successfully casting a ballot by mail in Pennsylvania last month. At least three weeks before the June 2 primary election, to be precise.

Voters whose mail ballot requests were processed after that point were less and less likely with each passing day to end up successfully voting, according to an Inquirer analysis of state data.

Before May 12, almost 90% of voters who requested mail ballots ultimately voted, and the vast majority did so by mail. But many mail ballot applications, almost two out of five, were processed within three weeks of the election. And for those voters, only about 76% ended up voting.

That’s a significant difference: Without that drop-off, about 92,000 more Pennsylvanians would have voted in the primary, according to the Inquirer analysis.

This year’s primary was the first election in which people were allowed under a new state law to vote by mail without providing a reason. Coupled with a coronavirus pandemic that made in-person voting riskier than normal, the new law sent the number of mail ballot requests skyrocketing. Every step of the process took longer than normal, with inundated county elections offices struggling to quickly process applications and print ballots. And mail delivery was uneven and often delayed, voters and elections officials across the state said.

While it’s impossible to know exactly why the voting rate dropped as mail ballot requests were made closer to election day, the data suggest elections officials and voting-rights advocates were right when they warned that the state’s mail ballot deadlines are too tight and were likely to disenfranchise voters.

“And the data now backs it up,” said Lee Soltysiak, Montgomery County’s chief operating officer and clerk of its elections board. “It’s not just a bunch of grumpy election officials wringing their hands.”

Montgomery County was one of six for which Gov. Tom Wolf extended the mail ballot deadline, and elections officials there ended up counting thousands of mail ballots under that order. Even so, the voting rate fell from 89.5% for voters whose applications were processed before May 12 to 75.9% for voters whose requests were processed later. That’s 7,100 votes in Montgomery County.

Voters have until one week before election day to request a ballot, and completed ballots have to be returned by 8 p.m. election day to be counted.

For many voters, elections officials said, there’s no way to receive their ballots with enough time to return them. And because of the pandemic, many of those voters might not choose to instead vote in person.

“It may be with all the good intentions in the world, making it so people can apply as late as possible, but those good intentions are disenfranchising voters,” said Al Schmidt, one of the three Philadelphia city commissioners who run elections. “It doesn’t matter what the intentions are when voters are disenfranchised.”

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Tens of thousands of mail ballots arrived after the deadline, with most of them counted under Wolf’s order but thousands more rejected.

To get a wider picture of voter behavior, The Inquirer combined a dataset of every approved mail ballot request for the June 2 primary election with the July 13 voter roll, which records the method by which a voter participated in the primary election. (Two counties, Northumberland and Susquehanna, were excluded from the analysis because they did not have data for the primary.)

Of the more than 1.8 million voters in the analysis, 1.09 million had their applications processed before May 12 and almost 976,000 of them ended up voting. More than 713,000 voters had their mail ballot requests processed on or after May 12, and 545,000 of them ultimately voted.

The analysis cannot show why voters did not cast ballots. Some voters mailed their ballots back and they arrived at county elections offices too late to count. Others may have given up after deciding their ballot could not be submitted in time. And still others may have tried to vote in person but ultimately did not do so.

“There is clearly a timeline problem — [but] I don’t think we have enough information to know the solution,” said Suzanne Almeida, the interim head of the good-government group Common Cause Pennsylvania.

Elections officials and voting-rights advocates have urged state lawmakers and the governor to quickly pass a law changing the voting deadlines, though there’s no consensus around a specific fix. Some propose widening the window by moving the application deadline earlier. Others say the deadline for returning ballots should be later, perhaps by allowing ballots to be postmarked by election day but received in the days after. Still others suggest a hybrid of the two or some other option.

There are also several lawsuits in state and federal courts over how Pennsylvania’s general election will be conducted, and some of those take aim at the ballot deadlines.

Without a policy change, county officials said, they would urge voters to request mail ballots earlier, devote more resources to processing ballots more quickly, install drop boxes and other ways for voters to return ballots, and try to work with the postal service to ensure fast or at least predictable mail delivery times.

Ultimately, though, they said a statewide fix is required.

“The one thing we are all asking for at this point is to move that deadline,” said Allegheny County Executive Rich Fitzgerald. “Then I think some of those problems can be fixed.”