Reporting by newsman Anthony Izaguirre of the voting team, and analysis by Chicago-based Pia Deshpande of the data team, revealed that Postal Service districts across the nation are missing the agency’s own standards for on-time delivery as tens of millions of Americans prepare to vote by mail – and the lag times are especially pronounced in key regions of some battleground states.

Postal Service delivery times, some of them obtained through a Freedom of Information Act request, indicate that the district covering Detroit and the eastern third of Michigan, the part of the state that is being most heavily contested politically, has the worst on-time delivery in the nation. Regions of Ohio and Pennsylvania show similar underperformance. Further, the data showed on-time delivery across the country dipping substantially in the weeks after Postmaster General Louis DeJoy took office in mid-June. While service began rebounding toward the end of summer, no Postal Service region is meeting the agency’s target of delivering more than 95% of first-class mail within five days.

The story concludes that the message to voters is clear: Mail your ballot early.