Jia Qinglin owes his political survival to former President Jiang Zemin, who took care to protect him when a corruption scandal enveloped his wife.
Some analysts said that Mr Jia's 2002 promotion to the Standing Committee was entirely due to Mr Jiang's patronage.
They also said Mr Jia was put there as a surrogate for Mr Jiang himself, to protect his patron's name and interests.
Mr Jia, 64, has been a close friend of Mr Jiang for decades, even acting as best man at his wedding, according to some reports.
Mr Jia was Party chief and governor of the southern province of Fujian when it was hit by a corruption and bribery scandal involving the Yuanhua group in the mid 1990s.
Dozens of senior leaders, including Mr Jia's wife, were implicated in the scandal, although she has always protested her innocence.
Despite this apparent set-back, Mr Jia was promoted in 1996 - on Mr Jiang's orders - to take over as Party chief in Beijing.