In the late 1970s, divisions over the FSLN's campaign against Somoza led Ortega and his brother Humberto to form the Insurrectionist, or Tercerista (Third Way) faction. The Terceristas sought to combine the distinct guerrilla war strategies of the two other factions, Tomás Borge's Guerra Prolongada Popular (GPP, or Prolonged People's War), and Jaime Wheelock's Proletarians. The Ortega brothers forged alliances with a wide array of anti-Somoza forces, including Catholic and Protestant activists, and other non-Marxist civil society groups. The Terceristas became the most effective faction in wielding political and military strength, and their push for FSLN solidarity received the support of revolutionary leaders such as Fidel Castro.