Hong Kong is to hold limited elections to appoint the 800-member committee that is to select the city's next leader.
The election committee, usually comprised of individuals sympathetic to Beijing, will choose Hong Kong's chief executive in March.
Some hope Sunday's poll will pave the way for a pro-democracy candidate.
James Sung, a political scientist at Hong Kong's City University, said: "The atmosphere so far is no good. Ordinary citizens have no idea there is an important election."
The poll will involve only about 200,000 franchised voters in 38 business and community sub-sectors.
The committee election process has long been criticised by democrats as most of Hong Kong's seven million inhabitants have no involvement.
Many hope that the elections for Hong Kong's chief executive will be more open this year as Donald Tsang, Hong Kong's incumbent leader who is backed by Beijing, is to be opposed by pro-democracy challenger, Alan Leong.
Leong, a legislator and barrister, has admitted his chances are slim, but it would be a major achievement for him to at least get on the ballot sheet, for which he will need to reach the threshold of 100 nominations from the election committee.
Priscilla Lau, a Hong Kong deputy to China's National People's Congress, said: "I think Beijing is worrying about some people thinking of this time nominating Alan Leong.
"Beijing would like to show absolute support to Tsang."
Some analysts have suggested a high voter turnout could favour the pro-democracy groups, but more than a quarter of the seats have already been returned uncontested in conservative sectors, with another 96 seats reserved for ex-officials, including Hong Kong deputies to Chinese political bodies such as the National People's Congress.
Sung said: "At the end of the day, I think Alan may have the chance ... but I'm not optimistic."