NEW: The USPS changed its rules on how it postmarks ballots.

This may affect elections at every stage at which there`s a mail deadline.

An underplayed one: VOTER REGISTRATION.

Many voters who send in their registration forms by mail could be postmarked late, missing out without realizing it.

In an Intense Election Year, New Post Office Rules Could Trip Up Voter Registration - Bolts
A change in how mail is postmarked could lead some voters to miss key deadlines, including voter registration. Advocates worry the people most affected will be those already facing voting barriers.

(boltsmag.org)