With Jon Kaiman identified as the leading candidate for the top job at the Long Island Power Authority, his departure as North Hempstead supervisor — if and when the time comes — has generated buzz of a behind-the-scenes rivalry in Democratic circles over who would succeed him. Those reputed to be interested include county legislators Wayne Wink (D-Roslyn) and Judi Bosworth (D-Great Neck). The pick to fill the vacancy pending a supervisor’s election would belong to the town councilmembers, a majority Democratic. Gerard Terry, Democratic town leader, is widely believed to favor Bosworth. Stay tuned.