Republican Donald N. MacKenzie, 45, of Oyster Bay, is running for a second term. He defends the administration's claims on lowering crime, reducing unemployment and cutting more than 2,000 public jobs. The focus of his first term has been district-specific: revitalizing downtown Syosset and looking at storm-water runoff that too often closes beaches in Laurel Hollow.

Democrat Dean E. Hart, 57, of Glen Head, is an optometrist making his first run for public office. He teaches ophthalmology at North Shore University Hospital in Manhasset and has owned insurance and import businesses. He wants to bring that expertise to government.

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Hart's desire for greater transparency, especially around the troubled Nassau contracting process, is compelling. However, MacKenzie seems more likely to solve practical problems. We'd like him to acknowledge and work on county budget challenges, and find his own voice to resist getting caught up in GOP talking points.

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Newsday endorses MacKenzie.