One poll suggested the opposition Pheu Thai party would win 313 seats, compared with 152 for the Democrats of PM Abhisit Vejjajiva.
Thai exit polls are not always reliable, correspondents say, but these reflect pre-election opinion surveys.
Pheu Thai is led by Mr Thaksin's sister, Yingluck Shinawatra.
'Much work ahead'When the exit polls were shown on television, Pheu Thai supporters erupted in celebration at the party headquarters in Bangkok.
Yingluck Shinawatra said: "Let's wait for the official results. I will tell you how I feel tonight."
But she said Mr Thaksin had already telephoned her.
"Mr Thaksin called me to congratulate me and encourage me. He told me that there is still much hard work ahead of us."
The BBC's Karishma Vaswani in Bangkok says both sides have vowed they will respect the result but there is concern that their supporters will not and that there could be a return to the violence of the past.
The past few years have seen street protests, airport closures, and clashes between the supporters of the two main groups, which our correspondent says have tarnished the country's economy and reputation for being a bastion of democracy in south-east Asia.
Last year, protesters shut down parts of Bangkok for two months in a bid to force the government to resign. When the army stepped in to clear the capital's streets it degenerated into violence, leaving 91 people dead.
Many of the red-shirt demonstrators were supporters of Mr Thaksin, whose government was toppled in a military coup in 2006.
'Very crucial'Official results are expected in the late evening.
But exit polls, released as soon as voting ended, suggested a big majority victory for Pheu Thai.
The poll for Suan Dusit university gave it 313 seats, with the Democrats on 152. A poll by Bangkok's ABAC university suggested a result of 299 seats to 132.
More than 40 parties fielded 3,832 candidates for the 500-seat lower house of parliament, the House of Representatives.
How the voting system works in Thailand, and why this election is so importantIn a two-tier system of voting, 375 legislators will be elected by constituency, while 125 candidates will be chosen from lists according to the proportion of votes each party receives nationwide on a separate ballot. There are some 47 million eligible voters.
Yingluck Shinawatra was one of the first to vote at a school in Bangkok. She smiled and showed her ID card to television cameras before casting her ballot.
She said: "Thank you, supporters, who have been so kind to me."
Our correspondent says Ms Yingluck is a political novice, and her popularity seems to rest on the fact she is campaigning on the policies of her brother, who many believe is Pheu Thai's real leader.
He is living in self-imposed exile in Dubai to avoid a corruption conviction, and has made it clear that he is keen to return to his homeland.
Mr Abhisit had also voted in Bangkok and urged people to "cast votes quickly because this election is very crucial for our country".
Continue reading the main story Sept 2006: Army overthrows government of Thaksin Shinawatra, rewrites constitutionDec 2007: Pro-Thaksin People Power Party wins most votes in electionAug 2008: Mr Thaksin flees into exile before end of corruption to trialDec 2008: Mass yellow-shirt protests paralyse Bangkok; Constitutional Court bans People Power Party; Abhisit Vejjajiva comes to powerMar-May 2010: Thousands of pro-Thaksin red shirts occupy parts of Bangkok; eventually cleared by army; dozens killedMr Abhisit had said a vote for Pheu Thai was a vote for Mr Thaksin, and pointed out the party's own slogan was "Thaksin thinks, Pheu Thai does".He said the country must "get rid of the poison of Thaksin".
If Pheu Thai's win is confirmed, analysts say all eyes will once again be on the military, which has regularly intervened in the political process. Army chief Gen Prayuth Chan-ocha on Thursday stressed that he would stay neutral.
Thailand has had 18 attempted or successful military coups since democracy was established in 1932.
Our correspondent says there is a lot at stake.
Whoever wins will have to bring a divided nation back together again, and try to heal Thailand's wounded democracy, she adds.
Send your pictures and videos to yourpics@bbc.co.uk or text them to 61124 (UK) or +44 7725 100 100 (International). If you have a large file you can upload here.
Read the terms and conditions
Comments
Post a Comment