That support was in part driven by his popularity among the public. Yet as recently as June last year, he was polling in the single digits. Since October, he has led in every poll.

Not everyone was happy. Some members of the business community had taken to saying their favoured candidate was 'ABC' - Anyone But CY. They feared Leung would show a populist streak in office and might retaliate against those who had tried to block his path to the top job.

Sing Tao News chairman Charles Ho Tsu-kwok, who supported the other pro-establishment candidate, Henry Tang Ying-yen, went to the extent of saying: 'I would vote for [pan-democrat] Albert Ho Chun-yan' ahead of Leung - who was a non-executive director of the company until December. 'I would not vote for Leung. I have no way to understand his personality and his political platforms ... At least Albert Ho will strive hard to liaise with the different parts of the society,' he said when asked whom he'd prefer if only Leung and Ho were left in the race.

'If there are two swimming pools, one clear and one turbid, which one will you jump into?'

And James Tien Pei-chun, honorary chairman of the pro-business Liberal Party, said he would rather cast a blank vote than vote for Leung.

'CY has changed a lot over the past six months,' he said. 'Those who just got to know him will be happy to have known this CY, but his old acquaintances will wonder: which is the real CY?'

People closer to the grass roots, like environmentalist and blogger Lam Chiu-ying and Society for Community Organisation director Ho Hei-wah tell a different story. They talk of a man with a 'caring heart' and 'courage to improve society'.

Born in 1954, Leung is the son of a policeman who had migrated to Hong Kong from Shandong province. Leung lived with his parents and two sisters in the Police Married Quarters in Hollywood Road, Central.

Anxious to get ahead, he and his sisters combined schoolwork with jobs making plastic flowers to supplement the family's income and save money for homes of their own.

He studied at Hollywood Road Police Primary School and King's College in Sai Wan before graduating from Hong Kong Polytechnic (now Polytechnic University) in 1974 with a higher diploma in surveying.

He then studied valuation and estate management at Bristol Polytechnic (now the University of the West of England) in Britain.

Teachers and classmates saw little in Leung to suggest he would rise to his present heights.

'Chun-ying studied hard, but he was not a very smart student of the sort who would attract the attention of teachers and classmates,' said Leung Chik-wing, who taught him geography at King's College in 1969.

His teacher recalls a boy who enjoyed sports, especially soccer. These days, Leung prefers the pool and is a keen swimmer. Gardening is his other well-known passion.

Peter Cheung Kwok-che, a schoolmate of Leung's at King's College and now a Labour Party lawmaker, said Leung did not stand out at school, but by the time the pair met again in the 1980s, there were signs of the impressive networking and career-building skills that would take Leung to the top.

'We were not close during our time at King's College. When we met again in the old boys' society - after he had returned from the UK - he had got a relatively good career and network,' Cheung said.

Leung's willingness to help the family of an ex-schoolmate who had died left an impression on Cheung that has lasted three decades.

'A schoolmate working for the police in the early 1980s jumped from the roof of Police Station No7 [Western Police Station],' Cheung recalled.

'Some old boys gathered to discuss the incident. We found it very suspicious, given that he was an only son and had a police background. CY was very forthcoming in using his network to help the deceased's family try to find the truth.'

Although Leung's contacts were ultimately unable to unearth the truth behind that mystery, Cheung said, Leung succeeded in using his networking skills to rise in the business world.

He joined the Hong Kong office of real estate consultancy Jones Lang Wootton in 1977, rising to become the youngest equity partner in the British company's 200-year history five years later, at the age of 28.

After branching out to form his own company, he rose to become chairman of real estate adviser DTZ Asia-Pacific, from which he quit in November to focus on his campaign.

Leung's political star was also rising, starting in 1985, when he was appointed to the Basic Law Consultative Committee. Three years later, he became the secretary general of the committee, which was charged with agreeing the details of the city's mini-constitution.

In 1996, Leung was named as one of the vice-chairmen of the preparatory committee overseeing Hong Kong's handover to China the following year.

He became the convenor of the Executive Council in 1999 and served in the role for more than a decade, until he stood down at the start of his election campaign last year.

Some question how Leung managed to rise so quickly. Could it be that he was a member of the Communist Party? Leung has always firmly denied it, but senior lawyer and former lawmaker Martin Lee Chu-ming thinks otherwise.

'It would be impossible for Beijing to have trusted him and put him in those crucial positions if he was not a Communist Party member,' Lee, the founding chairman of the Democratic Party, has said.

Speculation about Leung as a future chief executive candidate began even before Tung Chee-hwa was appointed to the newly created post before the handover. Leung famously answered the question by saying he would not run even in the 'nth' chief executive election - in other words, that he would never run.

That did little to ease speculation about his future. As long ago as 2004, the South China Morning Post reported that pundits believed an early chief executive race between Tang and Leung had 'already begun'.

However, Leung did not run when Tung resigned in 2005 nor when Donald Tsang Yam-kuen sought re-election in 2007.

Three years ago, Leung invited former lawmaker-turned-political commentator Allen Lee Peng-fei to a face-to-face meeting, the first time the two men had met in 29 years, and told him that he intended to run for chief executive.

Another veteran pro-Beijing politician, who did not want to be named, had a similar experience. The politician said Leung invited her for dinner in September 2009 after they had not met for decades.

Until scandals over Tang's marital infidelity and an illegal basement at a home owned by his wife derailed the favourite, Leung seemed a long shot.

But his path to the top job was itself hardly scandal-free.

Cheung, for one, thinks Leung owes Hong Kong an apology for the apparent conflict of interest when he served as a juror for the competition to design the West Kowloon arts hub despite one of the entrants having listed DTZ as a property adviser.

'He was negligent in declaring his interests [in 2001], so as a public figure, he should apologise to the public,' the former schoolmate said.

'But I feel he has been evasive in offering the full account of the story.'

Leung's claim that a DTZ director gave unpaid advice on land values without his knowledge to that entrant - later disqualified - has failed to win over lawmakers, and he is likely to enter office on July 1 still the subject of a Legco investigation.

A dinner on February 10 attended by rural leaders, members of Leung's campaign team and a businessman with alleged triad connections also sparked controversy. Leung's campaign denied any connections with triad members, and no one has admitted inviting the businessman to the dinner in Yuen Long.

Leung has been married to solicitor Tong Ching-yee for 30 years. They met while studying in Bristol.

Their three children returned from Britain for the election, and the family stood outside the polling station to canvass for votes during the second hour of voting yesterday.

Son Chuen-yan is a doctoral student in biology at Cambridge University. Elder daughter Chai-yan is studying at the London School of Economics and Political Science, and younger daughter Chung-yan is a first-year economics student, also at Cambridge.