I still maintain that it isn’t who casts the ballots, it is who counts them.
With electronic ballots, early voting, and importing voters (not to mention multiple votes), precinct by precinct, pad your tally.
The POTUS election is unique in that the electoral votes are the ones which matter, so hit the high population states, especially urban areas if you are a Dem, and target the electoral total.
The election would have to be won by your opponent by an overwhelming margin (landslide) for you not to prevail, and no one expects anything like that because all they have heard is how well you are doing in the polls.