>> Thailand enters calm before election storm

>> Thai polls begin with deep partisan division

Exit polls showed Yingluck Shinawatra's Puea Thai (For Thais) party winning a clear majority of parliament's 500 seats, paving the way for the 44-year-old business executive to become Thailand's first woman Prime Minister.

"I'll do my best and will not disappoint you," she told supporters after receiving a call of congratulations from her billionaire brother, who was ousted in a 2006 coup and lives in Dubai to avoid jail for graft charges that he says were politically motivated.

"He told me that there is still much hard work ahead of us," she told reporters.

With nearly all votes counted, Yingluck's party won a projected 261 seats with Prime Minister Abhisit Vejjajiva's Democrat Party taking 162, according to the Election Commission.

Abhisit conceded defeat. "I would like to congratulate the Puea Thai Party for the right to form a government," he said.

Exit polls by Bangkok's Suan Dusit University showed Puea Thai doing even better, winning 313 seats compared to just 152 for the Democrats, dismal enough to threaten Abhisit's job as party leader.

Yingluck's supporters were jubilant, erupting in roars and cheers as television broadcast the exit polls.

"Number one Yingluck," some shouted. "Prime Minister Yingluck" screamed others, as party members slapped each other on the back.

"Yingluck has helped us and now Puea Thai can solve our problems and they'll solve the country's problems," said Saiksa Chankerd, a 40-year-old government worker.

The results were a rebuke of the traditional establishment of generals, old-money families and royal advisers in Bangkok who loathed Thaksin and backed Abhisit, an Oxford-trained economist who struggled to find a common touch.

The size of Puea Thai's victory could usher in much-needed political stability after six years of sporadic unrest that featured the occupation of Bangkok's two airports, a blockade of parliament, an assassination attempt and protests last year that descended into chaotic clashes with the army.