The infighting in the Kerala unit of the Congress has turned into a serious power struggle as veteran K Karunakaran is exploring the possibility of joining hands with the Marxists to oust the A K Antony government.

Karunakaran's supporters say in the wake of the Congress candidate's defeat in the Ernakulam Lok Sabha bypoll, pressure is mounting on Chief Minister Antony to quit.

The Congress traditionally held the Ernakulam constituency, but this time the party's candidate, M O John, an Antony loyalist, was defeated by Sebastian Paul, an Independent fielded by the Left Democratic Front led by the Communist Party of India-Marxist.

Peeved that the party high command had not consulted him on John's candidature, Karunakaran had kept away from campaigning.

The veteran leader had also urged his supporters to openly campaign for the LDF candidate.

"Now that Antony has failed to make his candidate win, I feel it is a major verdict against his government. The chief minister should own moral responsibility for this defeat and quit," P C Chacko, former member of Parliament and a close aide of Karunakaran, told rediff.com

According to Chacko, the Congress is a divided house because the party leadership has "thrown away the idea of political consensus to the winds". "The Congress in Kerala cannot be strengthened by sidelining a veteran leader like Karunakaran," he added.

Following John's defeat, hundreds of Karunakaran's supporters are meeting the former CM with requests "to take appropriate political moves".

One of his supporters disclosed to rediff.com that Karunakaran is seriously talking to CPI-M leaders on the possibility of forming a new government.

The Karunakaran faction claims to have the support of 23 legislators in the 140-member Kerala assembly. Karunakaran's aides agree that it will be a mammoth task to overthrow Antony because he has two-third majority in the assembly.

"But there is no harm in trying to install a new government. We are sure many MLAs who are supporters of Antony will cross over to our group if Karunakaran goes in for an arrangement with the Marxist party. Everyone in Kerala is fed up with the Antony government," he said.

But Antony supporters said Karunakaran's ambition is "a pipe dream." "The Congress has lost in the Lok Sabha election because Karunakaran purposefully defeated the candidate. So now blaming Antony for Karunakaran's mistake is not correct," an Antony loyalist pointed out.

He said the Antony government now wants the high command to take stern disciplinary action against Karunakaran and his supporters.

"They are ruining the party in Kerala. The Congress high command cannot pretend to be sleeping now," he added.

Marxist leaders said the poll verdict is a vote against the government. "We want Chief Minister Antony to resign immediately. His government does not have any moral responsibility to continue," CPI-M leader and opposition leader V S Achuthanandan told rediff.com

Asked if the Marxists are ready for a power-sharing arrangement with Karunakaran, Achuthanandan said: "Wait for a few days."