People Power Party has re-nominated Samak Sundaravej for the prime minister's post despite strong objections from protesters and its coalition partners.
PPP's spokesman Kudeb Saikrajang said a majority of party members voted to reappoint Samak.
Samak is "the leader of our party so he is the best choice."
The spokesman was speaking after a meeting of PPP MPs at a Bangkok hotel.
Constitution Court on Tuesday disqualified him from the premiership for violating the constitution.
The meeting also assigned PPP Secretary General Surapong Suebwonglee to inform Samak the meeting's decision.
Earlier PPP MP of Ubon Ratchathani Chuwit Pitakpornpairob said Samak will have the final say on the re-nomination.
The Parliament is scheduled to convene on Friday to select the vacant top position. PPP's deputy leader Somchai Wongsawat is now acting prime minister.
"The meeting decides to nominate Samak in the parliament tomorrow. However it is up to Khun Samak whether he will accept the nomination or not," Chuwit said.