The Pheu Thai Party will gain the most from the Constitutional Court's ruling to use 100 as the divisor to calculate party-list MPs, but its ambitious goal of winning a landslide victory at the next general election remains in doubt.
In its ruling on Wednesday, the court endorsed the validity of the organic law on the election of MPs and cleared the way for the use of 100 as the divisor to calculate party-list seats at the next poll.
The judges decided that the process by which the bill came to be adopted by parliament was valid, and the contents of the bill did not contravene sections 93 and 94 of the charter.
As a result, the divisor of 100, which is preferred by major political parties like Pheu Thai, will be used in the calculation of party-list seats at the next general election scheduled to take place in May next year, provided the House completes its term.
The court's ruling was in response to a petition initiated by Dr Rawee Matchamadol, leader of the New Palang Dharma Party (NPDP).
Small parties, including the NPDP, prefer the divisor of 500 being adopted to calculate party-list seats as it will require fewer votes to acquire list-MP seats.
Based on voting figures in the 2019 general election, it is estimated that political parties would need around 75,000 votes to win a list seat if 500 were used.
However, by adopting 100, political parties would need to capture at least 350,000 votes.
The figure 100 is derived from the total number of party-list MPs, while 500 would include all of the constituency MPs as well.
Following the court's ruling, parliament can proceed to submit the bill to the government for further submission for royal endorsement.
It is widely agreed that the Pheu Thai Party will win the largest number of House seats under the two-ballot system and the new party-list calculation method.
Wanwichit Boonprong, a political scientist at Rangsit University, told the Bangkok Post that Pheu Thai will emerge victorious in the next contest but whether or not it can form a government is another story.
He said if the main opposition party does not win big enough or fails to secure support from other coalition parties, it is unlikely to form the next government due to the Senate.
The 250-member Senate will still be around to join MPs in selecting the prime minister as head of the government, and it will be a key factor in government formation, he said.
The analyst said that after the court ruling, partnerships between small and medium-sized political parties would begin taking shape, and defections would be a common occurrence.
Thanathorn Juangroongruangkit, chairman of the Progressive Movement, said the new party-list calculation is unlikely to benefit the Move Forward Party (MFP) because the number of party-list seats will be lowered from 150 to 100.
The MFP, which is a reincarnation of the Future Forward Party, was the biggest winner in the 2019 poll that used a single ballot.
The majority of the party's seats were from the party-list system.
Paiboon Nititawan, deputy leader of the ruling Palang Pracharath Party, expressed confidence that under the new system, the party, under the leadership of Gen Prawit Wongsuwon, would win the election and be the core party to form a government.