Trump separated himself from the pack in 2016 by campaigning on building the wall, deporting illegals, draining the swamp, and locking up Hillary.
If he tries running on the same or similar issues this time around, the stench of bullshit will be too much to ignore except for his most devoted followers.
IMO, he'll probably run on "I'm not Biden," and I'm sure with how bad Biden is, he'll win just off of that.
The sad part is, this will be another wasted election to try and get an actual change candidate who won't sell out as much. Too bad Rand Paul has a terrible sense of what grassroots Republican voters want. Last time around, he was pandering to try in bring in more black voters. Fucking eh, what a mess.
He can run on finishing the wall: no one in their right mind expected that to get finished in four years, and sane voters will find it perfectly reasonable if he promises to complete it in his second term.
With MAGA control of congress, the necessary bureaucratic purge and ramping up deportations will be much easier to achieve this time around.
He was also responsible for the best economy the US has had in this century, so if by "I'm not Biden", what he means is "I will at least do something to stop the bleeding after the current administration's attempt at economic suicide", then that will likely also be a winner.