The 59-year-old Lam, widely seen as China'spreferred candidate, secured 572 of the committee's 1,200 votes—just 29 votes shy of the 601 needed to win the job. Meanwhile, Tsang and Woo got 160 and 179 votes, respectively.
As a special administrative region of the mainland, Hong Kong is unable to democratically elect its own leaders so Beijing has final say on the matter.
Lam has a 95 percent chance of winning, Danny Gittings, associate professor at the University of Hong Kong, told CNBC on Thursday.
Hong Kongers seem to agree; a survey commissioned by the South China Morning Post (SCMP) last month revealed 65.9 percent of respondents believed Lam would win the race.
"Beijing has been quick to throw its weight behind Lam as the popularity of the region's pro-democracy candidates has grown," political intelligence firm Stratfor said in a Wednesday note.
Mainland officials reportedly met with Hong Kong's pro-China camp last month and conveyed Beijing's decision to promote Lam, even allegedly asked electors to change their votes in her favor, Stratfor continued.