Academics believe the Move Forward Party (MFP) will join hands with the Pheu Thai Party and small parties to form a government coalition.
They were asked to express their views after the Election Commission (EC) began counting votes after polling stations closed at 5pm on Sunday.
As of 9.11pm, the Move Forward Party had taken the lead in both the constituency and party-list races, followed by the Pheu Thai Party and the Bhumjaithai Party. The votes were still being tallied, with unofficial results expected around 11pm on Sunday, according to the EC.
Wanwichit Boonprong, a political science lecturer at Rangsit University, said the latest Suan Dusit Poll findings ahead of the election showed the MFP and Pheu Thai can form a coalition without the support of the Senate or the Palang Pracharath Party (PPRP).
But according to the Nida Poll, the PPRP and the United Thai Nation Party still have a chance, Mr Wanwichit said.
"As it happens, the liberals have won a victory over the conservatives. New generation people turned up in large numbers to cast their votes. They showed their desire for change as they are fed up with political conservatism," Mr Wanwichit said.
"I don't think the victory of the MFP will trigger any coup. But the party must compromise on certain conditions while it carries out what it can do first, such as economic policies.
"If they are wise, they will hand the defence portfolio to Pheu Thai which can liaise with the conservative bloc to show the MFP are ready to make concessions," Mr Wanwichit said.
But if Pheu Thai wins the most seats, it is still likely to work with the MFP. However, when it comes to the allocation of ministerial posts between them, it remains to be seen whether the MFP is willing to accept Pheu Thai's conditions, he said.
Olarn Thinbangtieo, a political science lecturer at Burapha University, said that if the MFP wins the most seats, it is expected to work with Pheu Thai and form a coalition government, with MFP leader Pita Limcharoenrat to be the new prime minister.
Pheu Thai may then have to make concessions to the MFP, which could have a negative impact on the planned return of fugitive former premier Thaksin Shinawatra, Mr Olarn said.
Another scenario is that Pheu Thai would refuse to form a coalition with the MFP and if the MFP fails to gather enough support from other parties, the MFP could end up in the opposition bloc while Pheu Thai will form a coalition with parties in the rival camp, such as the PPRP, Mr Olarn said.
Phichai Ratnatilaka Na Bhuket, programme director for politics and development strategy at the National Institute of Development Administration (Nida), held a similar view.
He said the mostly likely coalition will be made up of MFP and Pheu Thai, and the party that wins the most seats will have the right to nominate its PM candidate for a vote in parliament first.
However, if the two parties fail to gather the support of a combined 376 MPs, more than half of the combined 750 members of the Lower and Upper Houses, they may need to bring in other parties to reinforce the coalition, such as the Chartthaipattana Party, he said.
A coalition comprising Pheu Thai, the Bhumjaithai Party and the PPRP is also possible, which means the MFP will be forced into the opposition bloc, Mr Phichai said.
Kriengkrai Thiennukul, chairman of the Federation of Thai Industries (FTI), said if a new government is formed by major parties in the opposition camp, the new administration is likely to implement new policies, like an increase in daily minimum wage, and carry on with good economic development plans, initiated by previous governments.
He was commenting while the MFP and Pheu Thai parties were taking the lead during counting as of press time on Sunday.
Though an increase in minimum wage can relieve workers' burdens, it can cause a negative impact on labour-intensive businesses as it will increase their operating costs at a time of global uncertainties, said Mr Kriengkrai.
He is afraid the wage rise policy, if not gradually enforced, may cause some companies to consider relocating production bases to neighbouring countries.
The FTI chairman also wants the new government to continue key economic policies like the Eastern Economic Corridor (EEC) development scheme.
The government and business sectors have spent a huge amount of money developing infrastructure in the EEC zone. This job must continue as the EEC is expected to be a new economic driver of the country. The EEC covers parts of Chon Buri, Rayong and Chachoengsao, part of a proposed high-tech industrial hub.