Raised in central New Jersey, McCorkle began working in theater during high school. After graduating from Douglass College with a B.A. in theater, she went on to New York University to earn a graduate degree in theater education, with a focus on directing. In 1974, after a brief stint teaching high school English and working as a stage manager in summer stock theater, she was invited by Alan Wasser to join New York's legendary Broadway theater, The Circle in the Square. Working first as subscription manager, and then as an assistant to the artistic director, McCorkle found herself drawn to casting and began work as a casting assistant.
