A Wake County Board of Elections employee prepares a mail-in ballot to be sent out to a voter in September in Raleigh, N.C.(Matt Ramey)Relying on the U.S. Postal Service to return a mail-in ballot close to Election Day now comes with an additional risk for many voters — a late postmark that gets a vote rejected.
The risk stems from mailing system changes that began last year. And those changes have pushed some election officials to encourage vot…