The effort to attain votes for candidates is less important than the strategy of collecting ballots.
It should be emphasized; these are two distinctly different voting systems.
The system of ballot distribution and collection is far more susceptible to control than the traditional system of votes cast at precincts.
They probably mailed the ballots to all the dead old people they killed off in nursing homes in the 5 states they did that. PA, Michigan, New Jersey, New York, and can’t recall the other one. New Jersey maybe?