as with most of dems/china's coup schemes, everyone involved is likely already being monitored and hopefully it will be used to lock them up.
technology exists and has in part since at least 1975 to use a scheme such as vote by mail to create a federal database and reconstructed image of every ballot, complete with metadata and fingerprints; and to monitor and analyze the data in real time.
existing tech can use sensors and emitors to create images of the content of envelopes without ever opening them.
POSTAL SERVICE PHOTOGRAPHS EVERY PIECE OF MAIL IN THE U.S.
https://www.newsweek.com/postal-service-photographs-every-piece-mail-us-shares-agencies-request-it-280614
Postal Inspection Service's Monitoring and Control of Mail Surveillance and Mail Cover Programs
https://books.google.com/books/about/Postal_Inspection_Service_s_Monitoring_a.html
Mail Isolation Control and Tracking
https://en.wikipedia.org/wiki/Mail_Isolation_Control_and_Tracking