Claudia Swisher loves casting her ballot in person on Election Day, but this year COVID-19 health concerns are keeping her away from the polls.

In her lifetime, the 75-year-old Norman, Oklahoma resident has voted only four times by mail. She cast three of those ballots this year. Swisher also paid $100 to become a notary public to make it easier for her neighbors to comply with the absentee ballot notarization law in the state.

CNHI state house reporters and a data journalist spent collecting, organizing, and analyzing elections data from a number of key states across the U.S. to answer two broad questions: How have absentee and mail-in voting changed since 2016? And where are voters using the method more during the 2020 primaries?

The team gathered county-level voting and demographic data from state elections officials and the U.S. Census Bureau in eight states: Florida, Georgia, Indiana, Michigan, Minnesota, Ohio, Oklahoma and Pennsylvania. The first and most basic analysis examined differences in total mail-in and absentee votes to compare the two presidential election years. The results showed at least an additional 5.2 million mail-in and absentee votes were cast in 2020 primary elections when compared to similar 2016 elections.

Data depicting which parties used mail-in or absentee balloting was only available for four states. In two of them — Florida and Georgia — Republicans used mail-in voting more often than Democrats during 2020 primary elections. In Oklahoma and Pennsylvania the trend was reversed, and Democrats were more reliant on absentee and mail-in voting. The analysis used basic linear regressions to look for correlations between a county's partisan lean and voter behavior in the remaining states. In three of the four, counties with more Democratic voters tended to use absentee and mail-in balloting at greater rates.

Similar regressions examined correlations between demographic variables and voting behavior. The most consistent pattern, observed in seven of the eight states analyzed, is a relationship between higher median household incomes and increased use of mail-in or absentee ballots. In some states the relationship was weak, and in some it was strong, but in six of those seven, the positive correlation between voting behavior and income was statistically significant at the 95% level.

“I want to take away as many barriers as possible to vote because people who want to vote should have as many options as possible,” Swisher said.

All but a handful of states now allow widespread access to mail-in — or absentee — balloting, but voters nationwide find themselves navigating a complex patchwork of regulations that vary from state to state — everything from voter ID requirements to strict ballot deadlines.

And prospective voters face conflicting messages about whether their ballots will be counted amid concerns over U.S. Postal Service delivery delays, barriers to access in poorer communities and the potential for fraud, despite no significant evidence that is, has been or will be a problem.

Still, experts say mail-in ballots will play a pivotal role in the Nov. 3 election and warn the race may not be settled until days later or longer, as record-setting numbers of people vote by mail. In Michigan, by Tuesday afternoon — 24 days before the deadline — 2.6 million voters had requested absentee ballots. That's more than half the total number of voters who turned out in the state during the 2016 election.

The last presidential election was decided by margins of less than 2% in six states — Florida, Pennsylvania, Michigan, Minnesota, New Hampshire and Wisconsin. Pundits and policymakers differ on which states will swing this year, but some estimate the race could hinge on voters in eight, including Arizona, Florida, Georgia, Michigan, Minnesota, North Carolina, Pennsylvania and Wisconsin.

A CNHI data analysis showed voters cast ballots by mail in record numbers in the 2020 primaries when compared to 2016. Spikes in vote-by-mail turnout ranged from 2,758% in Georgia to 11% in Florida. Pennsylvania, which allowed anyone to vote absentee for the first time in 2020, saw a 1,616% increase in returned absentee ballot applications.

The increases in mail-in and absentee voting also held in places where total turnout fell.

CNHI's data analysis collected and analyzed county-by-county election data from eight states where mail-in or absentee ballot numbers were available. The findings show:

• In six swing states (Florida, Georgia, Michigan, Minnesota, Ohio and Pennsylvania), at least 5.2 million more voters used mail-in or absentee ballots in 2020 primary elections when compared to similar electoral milestones in 2016.

• Republicans relied more heavily on mail-in voting during 2020 primaries in two of four states where such comparisons were possible (Florida and Georgia). Prior to 2020, in Florida and Georgia's 2016 primaries, mail-in voting was roughly equally popular with Democratic and Republican voters.

• In seven of eight states examined, median household income of a county had a positive relationship with the use of mail-in and absentee ballots. Generally, the more wealthy a county, regardless which political party claims majority support, the more voters utilized mail-in or absentee ballots in 2020.

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