By Patpicha Tanakasempipat and Panarat Thepgumpanat
BANGKOK (Reuters) - Thai political parties on Friday held their largest rallies yet, two days ahead of the country's first election since a military coup nearly five years ago, but one that critics say will deny power to the most popular party.
Making his first appearance at an official campaign event, prime minister and junta leader Prayuth Chan-ocha was greeted with his nickname of "Uncle Tu" by supporters of a pro-army party that has nominated him as its prime ministerial candidate.
The opposition Pheu Thai party gathered separately in Bangkok before sunset for last-gasp campaigning.
Pheu Thai, removed from power by the military in 2014, is linked to ousted ex-premier Thaksin Shinawatra, a former telecommunication tycoon whose loyalists have won every general election since 2001.
Sunday's general elections have been cast as a high-stakes contest between democracy and military rule, but critics believe they have been rigged by a new army-backed constitution giving military-appointed officials a large say in the next government.
The military government says the new rules will bring stability after more than a decade of fractious, at times violent, politics.
Thailand's largest party, Pheu Thai, is leading the charge for a "democratic front" of parties against Palang Pracharat, a new military proxy party backing Prayuth.
"We are here to lift you out of despair," its main prime ministerial candidate, Sudarat Keyuraphan, told cheering supporters. "Happiness and a thriving economy both lie at the tips of your pens on March 24."
Thaksin, who has been in self-exile since a 2008 corruption conviction, attended his youngest daughter's wedding in Hong Kong on Friday. In a video clip put online by Thai media outlet, Khaosod English, he urged Thai guests to vote.
"We will win for sure," he said, without elaborating.
Without directly referring to the party, Thaksin said the wedding had to be held before the vote, or too many people would have turned out to attend, a hint at celebrations.
Seated by him in the clip was Thai Princess Ubolratana Rajakanya Sirivadhana Barnavadi, the elder sister of King Maha Vajiralongkorn, who shocked the country last month by accepting a Thaksin-linked party's nomination for prime minister.
The election commission quickly disqualified her and the party was dissolved for involving the monarchy in politics.
"CHOOSE PEACE, CHOOSE UNCLE TU"
Palang Pracharat adopted a new slogan ahead of the vote that features Prayuth's nickname, "Choose peace, choose 'Uncle Tu'."
Prayuth came on stage to cheers and music, waving to the crowd and accepting roses from supporters as a massive television screen showed a video of his years as the junta leader, harvesting rice and hugging children.
ADVERTISEMENTBackers of the military have warned Thailand could be plunged back into political unrest in case of a return to power for Pheu Thai, which has been under investigation for "outside influence", an inquiry that could see it disbanded.
Asked on Friday if another coup was possible after the poll, deputy junta leader Prawit Wongsuwan replied, "No, no, no."
Pheu Thai's long-time rival, the Democrat Party, also held a final rally in Bangkok.
Pro-establishment and pro-business, it hopes to hold the key to power after an inconclusive election, returning its leader, Abhisit Vejjajiva, to the prime minister's office he held unelected from 2008 to 2011.
ADVERTISEMENT"VOTE STRATEGICALLY"
Polls indicate Pheu Thai will again be the top vote-winner, and it hopes with its allies to make up the largest bloc in the 500-seat House of Representatives.
But that may not matter, because the new constitution written by the junta allows parliament's upper house, the 250-seat Senate, to vote with the lower house to choose the prime minister - and the Senate is entirely appointed by the junta.
The magic number of seats parties or alliances need to secure to form a government is 376, or one more than half the total number in the two houses of parliament.
With the military choosing all Senate members, pro-military parties would probably need to win only 126 seats in the House of Representatives to win a majority in a combined vote.
ADVERTISEMENTPheu Thai urged voters to take a strategic view.
"The rules in this election are designed to put the people at a disadvantage. If you don't want to give in to despair, you need to vote strategically," it said in a Facebook post early on Friday. "You need to vote for Pheu Thai for a landslide win!"
Parties and candidates are allowed to campaign until 6 p.m. (1100 GMT) on Saturday.
The next day, 93,200 polling stations will be open from 8 a.m. to 5 p.m. (0100 GMT to 1000 GMT).
The election commission has said unofficial results will be available three hours after the stations close on Sunday.
ADVERTISEMENT(Reporting by Patpicha Tanakasempipat, Panarat Thepgumpanat, and Panu Wongcha-um; Editing by John Chalmers and Clarence Fernandez)