Over 150,000 ballots that reached the post office by Nov. 3 were not delivered by Election Day.

Less than 85% of swing-state ballots that reached the post office by Tuesday were actually delivered by Election Day, The Washington Post reported.

More than 150,000 mail-in votes were affected by the US Postal Service's inability to process them on time, a product of delays in mail delivery that have significantly worsened since Trump donor Louis DeJoy became Postmaster General, The Post noted, citing court documents filed Thursday.

The post office's target for on-time ballot deliveries is 97%, but in Arizona, Nevada, Pennsylvania, North Carolina, and Georgia the on-time rate was just 84.6%.

Pennsylvania and North Carolina offer a short window for late ballots to arrive and still be counted, provided they were mailed no later than Nov 3. But neither Arizona nor Georgia count mail-in ballots that arrive after Election Day, in this case invalidating over 800 votes in each state, according to The Post.

The figures stem from a lawsuit brought in August by the NAACP and other civil rights groups, as Business Insider reported. That litigation aimed at ensuring the USPS would commit to delivering every mail-in ballot on time.

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