There are more than two years to go before Hong Kong acquires a new Chief Executive in place of Donald Tsang Yam-kuen. But already the administration has a lame duck look as Tsang gives the impression of tiring of being criticized and anxious to retire. Meanwhile the two most evident candidates to succeed him, Chief Secretary for Administration Henry Tang and executive council convenor Leung Chun-Ying are engaged in a very public battle for leadership in the opinion polls.

Not that the public has any direct say in who will eventually be chosen by a small group of carefully chosen Beijing-friendly selectors. It is also quite possible that Beijing has other candidates up its sleeve if one or both of the contenders makes some crucial errors over the next two years. However, the scope for new candidates to come to the fore is very limited given the undeveloped political system and reliance on either bureaucrats or Beijing-friendly members of opportunistic business families to fill top jobs. Elected politicians and successful professionals play minor roles.

Tang is very rich but his own business experience is limited. He is from one of the Shanghai textile families that were once – in the 1960s and 1970s in particular – keys to Hong Kong's prosperity. But the second generation has largely lived off selling textile quotas to companies that actually manufactured products, or from moving into the property business, an almost guaranteed path to greater wealth thanks to government land policies heavily influenced by the major developers. This pedigree may have more appeal to a princeling-friendly Beijing than outsiders would expect, especially as his Shanghainese background may find favor with a central government often suspicious of Cantonese.

Tang has a nice-guy image and an engaging smile. As a result he has largely escaped the public criticism that has fallen on Tsang, whose public approval rating was reported this week to have fallen to a low of 33 percent. However, Tang is not known either for decisive action or forward thinking. Indeed he may be best known for having been behind the abolition of taxes on wine – he has a fine personal cellar. In some ways he is similar to Tung Chee-hwa, the first post-handover chief executive, a likeable man from a well-known business family. But having had to remove the unfortunate Tung in 2005, Beijing may feel that Tang might prove equally vulnerable. He also lacks Tung's overseas connections and grandfatherly demeanor.

CY Leung is suspect because of what are generally agreed to be very close, but long-hidden ties to Beijing. He is a successful professional – a surveyor – but one so linked in the past to the property developers to be thought unlikely to want to challenge Hong Kong's oppressive and predominant commercial interest group. However, Leung has been making speeches about the need to address wide and rising income gaps and push ahead with long delayed plans for a minimum wage. In a recent article he noted the alarming statistic that 30 percent of Hong Kong people now earned less than in 1996, although GDP was supposed to have risen by 34 percent.

He also has the advantage of not being a minister and thus can make suggestions without having to implement them. (The executive council is only an advisory body). However he has little time for democracy and the legislature and so his would likely be more inclined to an authoritarian populism than Tang and so perhaps aggravate tensions over lack of popular representation and government accountability

Beyond these two names it is as yet a stretch to find any very obvious third candidates. Lifetime bureaucrats run most of the ministries. Of these the senior is Financial Secretary John Tsang Chun-wah who is doggedly competent but wholly lacking in imagination. Anyway, after Donald Tsang, Beijing may be wary of another bureaucrat from a system which resists change.

One other prominent person who may have an outside chance is Regina Ip Suk-yee, a former bureaucrat who was Secretary for Security under Tung but had to resign in after failing to force through legislation that many feared would undermine Hong Kong's liberties. She has since revised her views, her style and her once fearsome hairdo while remaining friendly-enough to Beijing. But she is regarded as a lightweight, memories of her ministerial record linger – and as a woman is unlikely to find favor among the almost exclusively male Beijing party hierarchy.

The other possible directly-elected legislator is Tsang Yok-sing. Formerly head of the Beijing-sponsored Democratic Alliance for the Betterment of Hong Kong (DAB) and now president of the Legislative council. He is personally well liked and can get along with individuals in the pro-democracy camp. But whatever his actual views, it is hard for him to gain broad confidence given a history of slavish following of the party line. Once a supporter of rapid movement towards democratic development he now supports minimal change to a system of functional constituencies whereby business and other narrowly-based groups back the government in return for favors. Nor is he seen as a decisive leader.

Beyond these names it is hard to find candidates. Andrew Li Kwok-ning who is retiring soon as Chief Justice, a post he has held since 1997. At 61 he is still young enough to be Chief Executive. He is highly regarded as intelligent and upright and comes from one of Hong Kong's leading families. However, it is doubtful if he is interested in the more exposed position of political leader and his determination to keep the judiciary independent runs counter to Beijing's preference for increasing executive authority at the expense of legislature and judiciary.

Another name which appeals to some is Victor Fung Kwok-king chairman of the huge Li & Fung logistics and trading group and who has chaired various bodies such as the Airport Authority. He has a genuine record of business achievement, is thoughtful and is well known outside Hong Kong. But he does not have many Beijing connections and is already 65.

There is a fundamental difficulty in arriving at anything more than a "least bad" choice. Hong Kong people mostly want more democracy and someone who will stand for the territory's interests more clearly than Tsang, often see as visiting Beijing to receive instructions. But more than ever Beijing seems to be looking to interfere in local decisions so it is not going to favor anyone who might try to follow an independent line.

Hong Kong also want someone more sympathetic to the needs of lower and middle income groups than shown by either the top bureaucrats or their allies among the big business groups whose profits are closely related to government decisions on land sales, utilities pricing etc. Beijing may be listening on this point as it realizes that further alienation of government from people could easily lead to a repeat of the mass demonstrations in 2003 which, along with subsequent government bungling, to the removal of Tung.

Someone who enjoys Beijing's confidence may be better able to represent Hong Kong than Tsang, whose colonial knighthood and much-advertised regular Catholic church attendance were viewed with suspicion. So having been given the job simply in the wake of Tung's failure and on the assumption that he was at least a competent bureaucrat he has had to prove his loyalty through subservience.

Some argue that Hong Kong would be better off with a senior figure from the party hierarchy, someone who had run a big province and had clout in Beijing. Such a person would be better able to defend Hong Kong's interests both from central interference and versus Guangdong authorities which pursue local self-interests under the guise of cooperation. However, that is not possible. The person must be from Hong Kong, according to the Basic Law, but, says Beijing, Hong Kong people cannot do the choosing.

A lot can happen over the next two years which will change the whole picture, removing some candidates from contention, bringing in new ones. But for now at least it looks like a contest between hereditary wealth and a self-made Communist party sleeper who appears to favor the Lee Kuan Yew style of government.