It depends on if he starts making promises to world leaders about what he will do if elected. That, in my understanding, is illegal.

Meanwhile, the non-esteemed New York Post suggests that Trump will let James grab Trump Tower, but it's probably leveraged and the value, if sold, isn't enough to meet the amount of the penalty. Trump’s failure to secure a bond could put his New York properties on the chopping block (from CNN) looks at other NY buildings also.