PHAYAO, THAILAND (REUTERS) - Like most in the sleepy town of Phayao in Thailand's northern mountains, schoolteacher Mu Suthibutr voted for parties loyal to Thaksin Shinawatra in election after election, even after the populist leader was ousted in an army coup and fled into exile.

But last Sunday, Mr Mu cast his ballot instead for the candidate of a party backing the ruling junta because he knows the candidate, a former Thaksin ally who switched sides, and thinks he "will be the most useful" for the town.

"Many feel that Thaksin will not be able to come back, so they have to vote for someone that they can depend on rather than what is in their heart," Mr Mu said.

The pro-junta party won in Phayao, the first time since 2001 that a Thaksin-loyal party has lost in a town that - like much of the north and north-east of Thailand - has long been a bastion of "red shirt" support for the former telecoms tycoon.

Phayao is part of a broader shift in Thai politics as it returns to an electoral process after nearly five years of military rule, one that may make the country even more difficult to govern.

For years, the South-east Asian nation has been divided between mostly rural and northern supporters of Thaksin, and his fierce opponents - mostly urban and middle class - who revile him as a corrupt demagogue.

Amid spasms of street protests, the rival camps became known as "red shirts" and "yellow shirts".

Now, with the military entrenched in politics and the emergence of a charismatic figurehead of democracy who reminds voters of a younger Thaksin, the country's political landscape is fragmenting.

Indeed, last week's election - the first since the 2014 military coup - has set the scene for protracted political deadlock because no one party won the majority of parliamentary seats required to rule.

In Phayao town, though, most people accept the result that gave its House of Representative seat to the pro-army Palang Pracharath party, which is seeking to keep coup leader Prayut Chan-o-cha on as an elected prime minister.

Voter accounts there of the pro-Thaksin Pheu Thai party's loss provide a snapshot of how Thaksin's seemingly unshakeable grip is loosening even in his political heartland after more than a decade in self-imposed exile following an earlier coup.

Thaksin did not immediately respond to a Reuters request for comment.

LOSING TOUCH?

Despite the opposition of the Bangkok-based "yellow-shirt" elite, parties loyal to Thaksin have won each election since 2001 thanks to his hold on the north and north-east. Thaksin still has legions of loyal supporters in these regions, but Pheu Thai's share of seats shrank in the latest election to 63.5 per cent from 80.2 per cent in 2011.

The loss of constituencies like Phayao town illustrates that Thaksin's absence, as well as recent missteps - one of his proxy parties nominated the king's sister as its prime ministerial candidate and was promptly eliminated - have cost him votes, one analyst said.

"Pheu Thai cannot take the north and north-east for granted," said Dr Titipol Phakdeewanich, dean of the faculty of political science at Ubon Ratchathani University.

Phayao, surrounded by farms about an hour's drive north of Thaksin's home city of Chiang Mai, is the main town in the province of the same name.

Townspeople often gather near a large lake in the city centre to feed fish that swim up to the banks or sit in cafes - and, after the election, they're happy to talk about politics.

One explanation several gave for the pro-junta Palang Pracharath's win here is that its candidate, wealthy local businessman Thammanat Prompao, is well known in the community and also chairman of a local football team.

Mr Thammanat, for years a prominent Pheu Thai leader, told Reuters he switched allegiance because he came to believe that if his former party won power, it would only bring more conflict.

He secured the constituency with 52,417 votes, compared to Pheu Thai's candidate's tally of around 21,971, according to results released on Thursday.

Phayao is not the only constituency where the junta's proxy party fielded a former Thaksin loyalist - about 30 of its candidates in 350 constituencies nationwide were former Pheu Thai parliamentarians or prominent supporters.

Pheu Thai's four-time parliamentarian from Phayao, Ms Arunee Chamnanya, says she lost her seat "because the electoral process was not a fair fight".

For example, Pheu Thai complained that it booked a local sports arena for a rally on Jan 10 but provincial officials revoked the permission a day before it was to be held.

"There has been an abuse of state power and usage of officials in the area," Ms Arunee said.

NEW VOICES

It is unclear how much of a discouraging effect such incidents had, but several former Thaksin voters said they had their own reasons for changing their minds.

The emergence of populist, youthful billionaire Thanathorn Juangroongruangkit, who promises an end to military "dictatorship", appears to have drawn votes away from Thaksin.

His Future Forward Party came third in Phayao town's constituency with 16,326 votes.

Ms Tai Puttasarn, 45, said she had always voted for Pheu Thai but this time she voted for Mr Thanathorn's Future Forward Party because he is a fresh voice offering a way out of the ruinous cycle of pro- and anti-Thaksin protests.

"Choosing Thanathorn felt like when I chose Thaksin in the past. They are both exciting politicians," she said.

Mr Suteep Thepawong, who sells food for passers-by to feed the fish in the lake, fondly remembers when then-prime minister Thaksin introduced cheap healthcare that improved life in the north.

But it has been more than 11 years since Thaksin left Thailand to escape a corruption sentence he said was politically motivated, and Mr Suteep felt it was time to move on.

"I didn't vote for Thaksin this time because he is no longer around," he said. "Thanathorn is here right now."

There are other explanations for the pro-army Palang Pracharath's stronger-than-expected showing. Few voters Reuters interviewed confirmed reports from elsewhere in the north of voter intimidation, but some acknowledged taking money.

One local fisherman said he was paid 500 baht (S$21) to vote for Palang Pracharath's Thammanat.

"I need to vote for him otherwise it would be dishonest," the fisherman said. "It would be a sin if I don't do what I promise. If I accept money, I have to follow through."

Mr Thammanat denied any vote-buying in his campaign.

Mr Suteep shrugged off the idea that vote-buying affected the results, saying most people just take the money and vote how they like.

But he said he was impressed by how many people voted for Mr Thanathorn's Future Forward even though it did not offer money.

"Palang Pracharath will not get the seat next time," he added. "I think Future Forward will topple them in the next election."