"I'm confident that, were I mayor, I would do some things differently than he has. But I think there's a world of difference between him and his immediate predecessor"

David Dinkins is revealing his confidence in his ability to do things in a different way if he were mayor. He is likewise implying that there is a considerable distinction between the current mayor and the previous one. This could be interpreted as a criticism of the present mayor, or a compliment to the previous one. It might likewise be seen as an indication of Dinkins' aspiration to end up being mayor and his belief that he could do a better task than the current mayor. It is also possible that Dinkins is merely acknowledging the distinctions between the 2 mayors and revealing his regard for both of them. Whatever the case, it is clear that Dinkins has strong viewpoints about the current mayor and his predecessor.