Polls opened in Thailand on Sunday in a general election defined by a three-way battle between the country’s conservative, progressive and populist camps, with no single party expected to secure a clear majority, prolonging the spectre of political instability.

Prime Minister Anutin Charnvirakul set the stage for the snap election in mid-December, amid a raging border conflict between Thailand and Cambodia, in what analysts said was a move timed by the conservative leader to cash in on surging nationalism.

At that point, he had been in power for less than 100 days, taking over after the ouster of premier Paetongtarn Shinawatra of the populist Pheu Thai party over the Cambodian crisis.

Pheu Thai, backed by the billionaire former Prime Minister Thaksin Shinawatra, who himself went to jail just days after his daughter’s removal, is down but not out, according to surveys.

But it is the progressive People’s Party, with its message of structural change and reforms to Southeast Asia’s second-largest economy, that has consistently led opinion polls during the campaign season.

“This election is about whether Thailand will get out of its rut, whether Thailand will break out of its political instability and economic doldrums that have persisted,” said Thitinan Pongsudhirak, a political scientist at Bangkok’s Chulalongkorn University. “My preliminary conclusion, I’m afraid to say, is that it will not break out.”

Although it has taken the fight to Anutin’s ruling Bhumjaithai Party and Pheu Thai, People’s Party may not have enough support to win a parliamentary majority on its own - raising the risk of repeating its predecessor’s fate.

Move Forward, the forerunner of the People’s Party, won the last election in 2023 only to be blocked from forming a government by a military-appointed Senate and conservative lawmakers, opening the door for Pheu Thai to take over.

This long-standing tussle between the powerful royalist-conservative establishment and popular democratic movements has created prolonged periods of uncertainty, punctuated by street protests, bouts of violence and military coups.

Constitutional referendum

Thai voters will also be asked during the vote to decide if a new constitution should replace a 2017 charter, a military-backed document that critics say concentrated power in undemocratic institutions, including a powerful senate that is chosen through an indirect selection process with limited public participation.

Thailand has had 20 constitutions since the end of absolute monarchy in 1932, with most of the changes following military coups.

If voters back the drafting of a new national charter, the new government and lawmakers can start the amendment process in parliament with two more referendums required to adopt a new constitution.

“I believe that the party that wins in the next election will have an outsized influence on the direction of constitutional reform, whether we move away from the junta-drafted constitution or not,” said Napon Jatusripitak of the Bangkok-based Thailand Future think-tank.

Different strategies

Bhumjaithai’s rise on surging nationalism unleashed by the Thai-Cambodia conflict - alongside the decline of Pheu Thai after its travails last year - has triggered a rash of defections and reshaped political battlegrounds, including vote-rich agrarian belts.

Some political parties have responded by drawing into their camps well-known local figures, including those from rival groups, aiming to capture personal loyalty networks that are key to winning in the hinterland.

The reform-minded People’s Party has also changed its playbook, diluting the progressive movement’s anti-establishment stance and bringing in outside talent to convince voters that it has what it takes to run a government.

Former Prime Minister Abhisit Vejjajiva has thrown himself into the mix, leveraging his personal appeal to revive his once moribund Democrat Party, which could emerge as a key force in post-election coalition talks.

Wish Witchudakornkul, a 20-year-old first-time voter, stood at the People’s Party final campaign rally in Bangkok on Friday, surrounded by a sea of supporters wearing orange - the progressive movement’s colour.

“I hope Thailand becomes fairer,” he said. “I want to feel that there is more democracy, and that people have greater freedom and better opportunities to live their lives.”