BANGKOK: Thailand on Monday awaited the results of its first election since a 2014 coup, with the junta primed to retain its grip on power after a vote that saw its main rival diminished but vaulted a new pro-democracy force into the kingdom's politics.
Election officials delayed without explanation a full announcement of preliminary results as a blizzard of complaints mounted over apparent mistakes in the count and possible irregularities at the polls.
Nearly 1.9 million votes had been invalidated with 93 per cent of votes tallied, the Election Commission said.
Earlier counts showed that in a handful of provinces more than half the ballots cast were invalidated.
The EC pushed back a preliminary announcement on the number of constituency seats won by each party to late Monday.
"Please wait. This is Thailand, we are not like other countries who have an election one day and form a government the next," said Jarungvith Phumma, EC secretary-general.
He sidestepped questions over wildly inaccurate poll returns reported late Sunday in several constituencies, as down to "human error".
Sunday's election -- seen as a referendum on the military -- was held under new rules written by the junta to ease its transformation into a civilian government.
Despite that headstart, analysts had not expected the army-linked Phalang Pracharat party to win the popular vote, given anger at junta rule and the enduring popularity of Pheu Thai -- the party of ex-premier Thaksin Shinawatra.
But preliminary figures showed Phalang Pracharat -- with 2014 coup leader Prayut Chan-O-Cha as its candidate for prime minister -- ahead in the popular vote.
It had racked up more than 7.6 million votes with more than 90 per cent of ballots tallied, giving any government it tries to form a claim to legitimacy.
That is nearly half a million more votes than Pheu Thai, which nonetheless was confident Monday it would still win the majority of lower house seats.
As rivals scrambled to seize the political momentum, Pheu Thai's prime ministerial candidate Sudarat Keyuraphan said her party had won the "mandate from the people" to form a government.
If the numbers play out, Pheu Thai will have to build a pro-democracy coalition, lassoing in Future Forward -- an upstart anti-junta party which has claimed over five million mainly youth votes.
Thaksin, the self-exiled billionaire ex-cop turned-Thai premier, who is at the crux of Thailand's political breakdown, reached out to shocked supporters in the pro-democracy camp as the results tipped against Pheu Thai.
"As long as we still have breath, we can not give up," he said in a Facebook post on Monday.
The EC has said it will finalise the results by May 9.
But questions over the count have billowed out, with social media ablase with allegations of vote buying, mass invalidation of ballots and bungling by polling staff across the country.
About 400,000 people signed a change.
org petition to dissolve the commission and more disputes are expected across the political spectrum.
A coordinator for Thailand-based election monitor We Watch said that voter education was "really insufficient" for the first election in eight years.
Voters were, for example, confused about "how to make the ballot valid, how to mark the ballot," We Watch's Chompunut Chalieobun told AFP.
Chompunut also said many monitors were blocked from accessing polling stations.
General Prayut's party appears set to get close to the 126 lower house seats it needs to secure a parliamentary majority, in combination with the 250-seat upper house Senate that is appointed by the junta.
"Every party has the right to gather 251 seats [to form a government]," Kobsak Pootrakool, spokesman of Phalang Pracharat told reporters.
"The people have chosen us."
But the vote has again revealed Thailand's old divisions between Thaksin supporters and arch-royalist, conservatives who look to the army for stability.
On the eve of the poll, Thailand's King Maha Vajiralongkorn issued a cryptic statement urging people to support "good" leaders against those who create "chaos."
The rare statement came hours before polls opened.
Thailand's monarchy is protected by harsh royal defamation laws and is nominally above politics.
But another royal command in February torpedoed the candidacy of the king's elder sister Princess Ubolratana for prime minister via a party linked to Thaksin.
Thaksin was ousted in a 2006 coup and has lived in self-exile since 2008.
The administration of his sister Yingluck was also the victim of a 2014 power grab by the military.