The re-election of the tycoon-turned-political heavyweight was virtually assured from well before the campaign season, but few dared predict his win could be so one-sided.

Should the television exit polls prove accurate, Thaksin's Thai Rak Thai party has won an unprecedented 399 of parliament's 500 seats.

"It was more than we expected, it was a landslide," Prapat Thepchatree, director of the centre for international policy studies at Thammasat University, told AFP of Thaksin's victory.

"I think it will make him more confident. He will say this is a strong mandate to do whatever he wants, with more centralisation of power," Prapat added. "Whether it's good for Thailand or not, it's difficult to say."

Thaksin, who swept into office in 2001 by promising to improve the lot of impoverished farmers and villagers, intends to push his political agenda in a second term.

He has generally received high marks for implementing his proposals, even as a string of crises demanded his government's urgent attention -- from outbreaks of SARS and bird flu, to a bloody Islamic insurgency and the tsunami's unprecedented devastation.

The extent of the win ensures that Thaksin's Thai Rak Thai will be able to govern outright, shedding its outgoing coalition partner party Chart Thai.

"The margin of victory indicates we are still in an unconsolidated democracy. Populism is still the key to victory, and the democratic principle of checks and balances has not yet fully emerged in this election," said Panitan Wattanayagorn, a lecturer at Chulalongkorn University.

Thaksin had come under fire from critics within and outside Thailand for being too authoritarian. Analysts fear that his huge victory could embolden him further.

"I think the management style of Thaksin could become even more pronounced, with centralised bureaucracy and administration," said Panitan. "If not controlled, it would become a centralized democracy and that may create unintended consequences."

By being shut out of any effective parliamentary censure of the premier, civil society could resort to "checks and balances outside the parliamentary system", including the use of populist upswells such as those seen recently in Ukraine, or in recent years in the Philippines, he said.

Giles Ungpakorn, also a lecturer at Chulalongkorn, said civil society and human rights could suffer under a stronger Thaksin regime.

"I think the Thai people were the losers in this election," Giles told AFP.

"This government has several problems including human rights violations stemming from the drug war, and Tak Bai and the Krue Se mosque," two spots in the south where authorities used excessive force to quell unrest, he said.

Thaksin's drug war left some 2,275 suspected drug offenders dead in apparent extrajudicial killings over four months in 2003.

A second Thaksin term "may lead to more human rights violations as the government will think people do not care about the past problems."

Thaksin's overwhelming victory also drove a stake into the heart of the main opposition Democrat Party, which had been aiming to secure 201 opposition seats, the minimum needed to censure Thaksin in parliament. They are projected to earn 80.

"The Democrats will have to go back to the drawing board for a new structure, new campaign and new candidates. They have to reinvent themselves," Panitan said.

Prapat said Thaksin's sweeping reelection signaled the likelihood of a long rule for Thailand's strongest-ever civilian leader.

"I think so, unless he makes some big mistakes," he said.