John Joseph Marchi (May 20, 1921 – April 25, 2009) was an American attorney and jurist who represented Staten Island in the New York State Senate for 50 years. Marchi (pronounced MAR-key), a Republican, retired on December 31, 2006, from the seat that he had held since January 1, 1957. He was the Republican nominee for Mayor of New York City in 1969 and 1973.