He should say "I've instructed my departments to compile a list of every communist, trans person, Palestinian, BLM activist, and I'm going to leave that list on my desk January 19th regardless of who's term starts the following day. Which president do you prefer has that list?" you know Blue MAGA would be ecstatic if he did that.
Trump will already have that list if elected regardless, by merit of entering the same office that Biden used to assemble the list. Real blackmail is the security state shit he's already been doing.