Due to the merger with the ASP, from 1977 it has also been the ruling party in Zanzibar, though there its grip on power has been more contested since the mid 1990s by the Civic United Front (CUF) which was later superseded in dominance on the islands by the Alliance for Change and Transparency (ACT).

This changed on July 1, 1992, when amendments to the Constitution and a number of laws permitting and regulating the formation and operations of more than one political party were enacted by the National Assembly.

Originally a champion of African socialism, upholder of the system of collectivized agriculture known as Ujamaa and firmly oriented to the left, today the CCM espouses a more mixed economic approach.

On 31 October 2010, Jakaya Kikwete was reelected president with 61% of the vote,[9] while CCM obtained 186 out of the 239 directly elected seats.

However, the election was held in the midst of significant democratic backsliding and repression, as Magufuli's presidency was characterized by unprecedented attacks on the opposition, civil society and press.

[11] Samia Suluhu Hassan is the current Chairperson of the Chama Cha Mapinduzi following the death of John Pombe Magufuli, the former Chairman and President of United Republic of Tanzania.