Ousted premier Thaksin Shinawatra and the Chartthaipattana Party have backed the move by 60 senators to submit three bills to amend the constitution by sections.
A source in the ruling Pheu Thai Party said yesterday Thaksin Skyped in to the party meeting yesterday and gave his support to the proposed amendment.
The source said the former premier felt amendments by sections were more realistic than changing the entire charter, which might run into legal problems with the Constitution Court.
Rewriting the entire constitution also put the parties seeking the amendment at risk of dissolution.
The source said Thaksin feared this could lead to the government's collapse.
Chartthaipattana also agreed with the senator group led by Nonthaburi senator Direk Thuengfang, former chairman of the Reconciliation Committee for Political Reform and Constitution Amendment, which wants sections 237, 68, 190 and 117 rewritten.
Mr Direk said the senators want to change the law so the Constitution Court will not have the authority to take up on its own accord cases related to sections 237 and 68 of the charter.
The sections involve the dissolution of political parties and the banning of party executives from political positions if they are found guilty of electoral fraud.
The senators also pressed for a change in Section 190 to do away with the requirement that all contracts with other countries must undergo parliamentary consideration. Critics say this has led to delays in the government's work.
The group is also proposing amending Section 117, which covers the senator selection process, with Mr Direk saying all 200 senators should be elected.
The senators are likely to forward three bills to amend the four sections to parliament today. Amendments to sections 237 and 68 will be proposed under one bill, Mr Direk said.
Former prime minister Somchai Wongsawat also backed amending the constitution by sections.
He said this is allowed by law.
Chartthaipattana spokesman Watchara Kannikar said the bill now stalled in parliament, which is intended to pave the way for the entire charter to be redrafted, is highly contentious and could spark a new round of political conflicts.
But amendments by sections would more acceptable to the public and even the opposition Democrat Party, he said.
Chartthaipattana's 19 MPs will join the 60 senators in submitting the bills today.