Since its formation, the PAP was divided into the Lee Kuan Yew camp and the left-wing camp led by Lim Chin Siong. The common ground of anti-colonialism and independence of Singapore was the basis for the co-operation between the two camps. Differences in their mass bases also encouraged such co-operation. During the early years, the left-wing camp mainly commanded support from the Chinese masses, rural people and trade unions, while support for Lee Kuan Yew's camp was mainly found in the English-educated community. With the support of the working class, the PAP won the third-most seats in the 1955 election and formed the main opposition. In 1959, with the support of the trade unions, the PAP won the election and formed the Government under Lee Kuan Yew. However, the two camps were ideologically and politically different in nature. During its formative years, the left-wing members already showed their dissatisfaction with the policies carried out by Lee Kuan Yew and his failure to fulfill his promises to help secure the release of the left-wing political detainees. Finally, the contentious issue of merger with Malaysia triggered the split within the PAP.