A new study suggests some voters in Wisconsin, particularly members of minority communities in that perennial tossup state, may lose their voting rights thanks to flaws in the state's process for maintaining registration lists.

At least 4 percent of Wisconsin voters' registrations were incorrectly flagged as out of date in 2018 because they were suspected of having moved but had not done so, Yale University researchers found.

Their report offers a number of caveats that demonstrate the incorrect labeling is likely higher than 4 percent. And in a place where the state Supreme Court is considering whether to purge 129,000 voters — and where the last two contests for presidential electors were each decided by fewer than 25,000 ballots — every registration is critical.