"Poor Darrell Hammond. What's he going to do when I leave office?"

This quote by William J. Clinton is likely referring to the comic Darrell Hammond, who was understood for his impersonations of Bill Clinton throughout his time in office. The quote indicates that Clinton is worried about what Hammond will do when he leaves office, as Hammond's impersonations of Clinton were a big part of his comedy act. It might be translated as Clinton feeling a sense of obligation for Hammond's career, as his impersonations of Clinton were a large part of his success. It might likewise be analyzed as Clinton feeling a sense of appreciation for Hammond, as he was able to record Clinton's mannerisms and speech patterns so precisely. Eventually, the quote suggests that Clinton knows the effect his departure from workplace will have on Hammond's profession, and is concerned for his future.