During his time in Guangdong, which borders Hong Kong, Wang made his mark by pushing an upgrade of rusting industries and touting socially inclusive policies.
Wang was passed over for promotion to the Politburo Standing Committee in 2012, but as vice premier he helped oversee China's external economic relations including with the United States.
YOUTH LEAGUELike Li Keqiang and Vice Premier Hu Chunhua - another premiership contender - Wang has ties to the Communist Youth League, a faction seen to be a rival to Xi's.
In recent years under Xi, Wang has seemingly tempered his reformist tendencies, echoing the party's tough line on sensitive political issues including Taiwan, Xinjiang and Tibet, while expressing support for Xi.
Register now for FREE unlimited access to Reuters.com RegisterReporting by James Pomfret; Editing by Tony Munroe and Lincoln Feast.