The New York City mayoral election of 2001 was held on November 6, 2001. Incumbent Republican mayor Rudy Giuliani could not run again due to term limits. As Democrats outnumber Republicans by 5 to 1 in the city, it was widely believed that a Democrat would succeed him in City Hall. However, businessman Michael Bloomberg, a lifelong Democrat, changed his party affiliation and ran as a Republican. Mark J. Green narrowly defeated Fernando Ferrer in the primary, surviving a negative contest that divided the party. A number of factors led to Bloomberg's ultimate victory in the general election, 50.3% to Green's 47.9%.