What were the leaders of political machines called?

The leaders of political machines were commonly referred to as "bosses." These bosses wielded significant influence over political processes and often controlled party nominations, appointments, and services in exchange for votes and loyalty from constituents. They operated mainly in urban areas during the late 19th and early 20th centuries, leveraging patronage and a network of loyal supporters to maintain power. Prominent examples include figures like Boss Tweed in New York City.