All eyes are on Prime Minister Prayut Chan-o-cha, chief strategist of the United Thai Nation Party (UTN) to see if he will be listed first in the party-list system. The party will make its decision known to the public on Saturday.
In the 2019 polls, Gen Prayut aligned himself with the Palang Pracharath Party (PPRP), which nominated him for prime minister, but he did not stand in the polls and was not a party member.
Political analysts say that this time round, Gen Prayut, the UTN's presumptive prime minister candidate, will be forced to engage by contesting the election in the party-list system.
Somjai Phagaphasvivat, a former lecturer at Thammasat University's faculty of political science, said Gen Prayut is not constitutionally required to contest the elections, but he is likely to do so to put all criticism to rest.
"Legally it's not necessary, but he will have to be the first party-list candidate for political reasons. He has only two years to serve as PM [due to term limits as defined by the court].
"And if you have noticed, he has engaged more with the party and joined its rallies,'' said Mr Somjai.
He ruled out the possibility of Gen Prayut contesting the elections in the constituency system, saying the party-list system has virtually no risk, especially if Gen Prayut is first on the list of candidates.
Jade Donavanik, dean of the law faculty at Dhurakij Pundit University, said whether Gen Prayut likes it or not, he cannot afford to stay aloof as he did previously with the PPRP.
The prime minister will have to run for a House seat, and given Gen Prayut's lack of canvassing experience and low tolerance for fools, it is best for him and the party if he contests the party-list system, he said.
"If he doesn't run for a House seat, he could face the same problem he did with the PPRP.
"However, it also depends on how the UTN members think about his role," he said.
Throughout his time with the PPRP, Gen Prayut was often chided by party insiders for keeping his distance from the party.
He even faced a plot to oust him from the job.
Although he has joined the UTN as its chief strategist and announced his intention to seek re-election as prime minister, Gen Prayut has left people in the dark as to whether he will run for a House seat.
The issue caught the public's attention after Poon Kaewparadai, a potential UTN candidate in Nakhon Si Thammasat, declared on Facebook on Tuesday that Gen Prayut would contest the May 14 polls and he would be No 1 candidate in the party-list system.
The post was removed on Wednesday morning amid reports that key UTN figures felt uncomfortable because Gen Prayut has not made his decision known himself.
The UTN is scheduled to introduce its constituency and party-list candidates, prime ministerial candidates and policy platforms on Saturday after a general assembly, according to a party source.
Gen Prayut will take part in the event.
The party will unveil its economic team today at the party's headquarters, with Energy Minister Supattanapong Punmeechaow and Thai trade representative chairman ML Chayotid Kridakorn expected to be named, according to political sources.
The UTN's strategic committee is also scheduled to meet today and the premier has taken leave from government duty to join.
PPRP leader Gen Prawit Wongsuwon refused to say if he himself would be a party-list candidate, adding the matter would be considered by the party's executive board.