News USPS Service blows deadline to check for missing ballots. About 300,000 can’t be traced November 3, 2020Dinah Voyles Pulver, USA TODAYComments Off on USPS Service blows deadline to check for missing ballots. About 300,000 can’t be traced The window is closing fast. The deadline for mail-in ballots either ends as the polls close tonight or has already passed in 29 states.