“Your call gave me a boost,” reads a letter from a young Barack Obama. It was April 14, 1984, and Mr. Obama had transferred to Columbia University in New York City as a junior three years earlier. The letter was addressed to Alexandra McNear, his girlfriend at Occidental College in Los Angeles, where he had transferred from. This is one of a series of handwritten notes that have been obtained by Emory University’s Stuart A. Rose Manuscript, Archives and Rare Book Library in Atlanta and will be available to the public for the first time.