In a general election, how do you know that one side or the other is trailing in mail in ballots? Are the envelopes not the same for R vs D?
I dunno....I know they’d be identifiable in a primary, but for general election ?
I think when a mail-ballot is returned, the voter who sent in the ballot has their record flagged in the voter registration database as having voted. The voter’s party identification is in their voter record, so it’s easy to tally Dems, Indies, Republicans that have voted.