Thanks. Do you have any idea of the ethnic background of their membership? Like how many of them are ethnic Nepalis, and how many are from other ethnic groups?
There are hundreds of ethnic groups, but the country can be divided into 3 basic groups: Indo-Nepalese, Tibeto-Nepalese, and those descendants of ancient inhabitants of Nepal(mostly mixed Indo-Tibetans).
Indo-Nepalese, who form the slight majority, can be divided into 2 groups - mountain folks(Paharis) and plain folks(Madhesi or Madhya Desis). Although both are immigrants from India, Paharis migrated centuries earlier. Madhesis are relatively recent arrivals who started inhabiting the Terai plains after malaria was contained. Paharis have pretty much all the power and Madhesis are seen as Indians more than Nepalese. Interestingly, The Maoist leadership is 60% upper caste Pahari who want to amend past injustices by the feudal society.
Tibeto-Nepalese can be divided into hundreds of small groups such as Rais, Limbus, Tamang, Bhotiyas, Sherpas etc. Some of those groups are successful, while some are piss poor peasants. Most of Maoist foot-soldiers are from this group.
The third group descended from ancient inhabitants, like Newars and Sakyas. Groups like Newars who inhabited Kathmandu valley are extremely successful and rival Paharis in power and influence. They are the most business oriented and least into Maoism.