When the Labour Party was taken over by Chinese-educated members with more leftist views—eventually leading to the party's deregistration by the government, Tan left the party to form Gerakan, with the objective of attracting Malays away from race-based parties such as the United Malays National Organisation (UMNO), a major party in the Alliance catering to the Malay majority of the population. Gerakan, together with the Democratic Action Party (DAP) which took similar stances to Gerakan, were very successful in the 1969 general elections, and appeared to be on the verge of denying the Alliance the 2/3 Parliamentary majority required to amend the Constitution. In Selangor, Tan's home state, the State Assembly was tied between Alliance and opposition assemblymen.