Jason Lee / Reuters

Chinese President Hu Jintao, left, applauds as former Chinese President Jiang Zemin waves at the opening ceremony of the 18th National Congress of the Communist Party of China at the Great Hall of the People in Beijing, on Nov. 8, 2012.

As China's Communist Party opened its 18th Congress in Beijing, outgoing President and party chief Hu Jintao was the first senior leader to enter the Great Hall of the People, greeted by thunderous applause from over 2,000 delegates as he walked to his front-row seat.

Hu was followed closely by a man who hasn't held a formal position of power in China for a decade.

Former president Jiang Zemin, 86, his hair dyed walnut brown, shook hands with other comrades and smiled as he entered ahead of the rest of China's core leadership, including Xi Jinping, the anointed next party general secretary and president.

The procession unambiguously validated Jiang's position at the pinnacle of China's politics, and he has worked assiduously to make sure his influence will be felt throughout the next leadership, which will be unveiled publicly on Thursday.

"He's still very much the power behind the throne," said Hong Kong-based China expert Willy Lam, who has written a book on Jiang.

As China undergoes its current leadership transition, Jiang has emerged as a critical power broker whose behind-the-scenes influence brings fresh uncertainty, and could hobble the new ruling elite's attempts to pursue reforms.

Part of the motivation for his deep involvement in China's imminent leadership transition, party insiders said, is personal. He wants to make sure his two sons, both of whom are successful businessmen, are protected at a time of enhanced scrutiny of the wealth accumulated by the families of the country's top leadership.

Slideshow: The reign of Jiang Zemin

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Details of Jiang's backroom dealings also reveal, sources said, his complicated relationship with Hu. They are not all-out rivals, but neither are they firm poltical allies.

Earlier this year, Jiang was instrumental in the demotion of Ling Jihua, one of Hu's closest allies, after reports that Ling's son was killed in a car crash involving a luxury sports car in March, sources said.

"Jiang asked Hu whether Ling Jihuawas still fit to be director of the (party Central Committee's) General Office after the accident," one source told Reuters, referring to the key role overseeing logistics and liaising with senior leaders.

"Ling Jihua was demoted after that."

Vigorous return to politics
Jiang has immersed himself in high level politics with renewed and surprising vigor this year after several relatively quiet years since the previous party congress in 2007.

Last year, rumors swirled that he was seriously ill, and a Hong Kong television station reported that he had died.

In recent months his public appearances have been select but poignant, including a Johann Strauss musical performance at Beijing's National theatre in September. Overall, in the past year, there have been more public Jiang sightings than at any point since his retirement.

The elevated public profile, party insiders say, mirrors the clout Jiang wields, or wants to be perceived as wielding, behind the scenes. The clout became apparent when Beijing was in upheaval over the scandal surrounding party heavyweight Bo Xilai.

Jiangwas consulted on how to deal with the scandal, which culminated in Bo being expelled from the party and facing possible charges of corruption and abuse of power. Bo's wife has been convicted for the murder of a British businessman.

Jiang is an adviser (to Hu), a (still) very influential adviser," a second source with ties to the leadership said.

"Jiang was consulted on how to handle the Bo Xilai case."

He has also been deeply involved in selecting the next Politburo Standing Committee, the country's supreme decision-making authority, that will be unveiled after the congress.

Jiang, along with Huand anointed leader Xi, helped draw up a seven-member "preferred list" ahead of the once-in-a-decade leadership transition, three sources with ties to senior party leaders told Reuters.

"Jiang and other party elders have veto power over standing committee nominees," one source told Reuters. Two high profile allies of President Hu — reformist Guangdong party boss Wang Yang and Li Yuanchao — may be passed over.

But sources with leadership ties said Huand Xi are pushing for landmark multi-candidate elections for at least the Politburo — and possibly the standing committee — throwing the "preferred list" into uncertainty.

The outgoing president is often depicted by foreign media as a rival of Jiang's, pitting Hu's so-called Youth League faction against Jiang's Shanghai faction. Party insiders told Reuters that their relationship is more complex than that. One source likened them to the board chairman and president of a corporation.

While Jiang does not meddle in the day-to-day running of the country, Huhas had to consult him on major political and policy decisions, sources with leadership ties said.

That arrangement will almost certainly continue under Xi once, as expected, he takes over as the party's new general secretary. Xi owes his political rise to Jiang, who marked him early on as a potential leader.

Protecting political legacy and family
Jiang has fought to maintain his political clout for two main reasons: to avoid any adverse political repercussions for his family or allies once he finally does pass from the scene, and to preserve what he sees as his political legacy.

Jiang's eldest son, Jiang Mianheng, is a prominent businessman with companies in various sectors from microchips to telecommunications and runs Shanghai Alliance Investment. His lower profile younger son, Jiang Miankang, is director of a Shanghai-based urban development research center.

His Harvard-educated grandson, Alvin Jiang, meanwhile, is a founder of Chinese private equity firm Boyu Capital, which received seed money from Hong Kong tycoon Li Ka-shing.

Jiang "will need powerful people to support his family'' once he's gone, said Lam. "Xi will ensure that no one touches his two sons."

Some party insiders believe Jiang is also seeking to protect his political legacy. He pushed hard for China's WTO accession in the 1990s, and first opened the door for private businessmen to join the Communist Party, against strong internal opposition.

Most view his time in office as a period of successful economic liberalization, though he's not believed to have much sympathy for political reform.

"When you've got a lot of uncertainties regarding the old generation of leaders still lurking behind," said Steve Tsang, a China political specialist at Nottingham University, "then it becomes that much more difficult, (and takes) a bit longer, before the new leadership decides whether it can take bold actions."

As long as Jiang is alive, analysts said, Xi had better get used to his presence. "As long as he is healthy, he won't give up his influence easily, he'll continue to exert it," said Jin Zhong, editor in chief of Open Magazine in Hong Kong, which specializes in China politics.

"This is China's greatest tragedy. Its reliance on dictators rather than the rule of law and democracy."

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