I wouldn't put it past Carlson to leave media and run (he'd have to).  That said, I don't think he'd win.  I don't think he'd be able to connect to the working class vote that Trump somehow (inexplicably) tapped into.  Am under no illusion that the Trump movement just ceases to exist, but as mentioned before, once the election gets certified and he's officially a "loser," some of its energy gets siphoned out.  Further, he's really too old to mount something next time (even though he would be the same age as Biden is now).  I just don't believe it would happen.  The way the new administration wins is to carefully and smartly cement certain policy gains.  They don't win if they tack too quickly to the left.  That would re-activate the opposition present in the Trump movement.