The green signal has been given to the Chief Minister to expand his Ministry and all of them are likely to take oath on Saturday, the sources said.
The sources, however, expressed doubt whether any defeated leader will be inducted in the Ministry.
KPCC Chief G Parmeshwar and senior leader C M Ibrahim are among those who have lost in the polls.
The sources said that the party leadership has suggested to Siddharamaiah not to induct a full fledged Cabinet keeping about 10 portfolios vacant.
V Sreenivasa Prasad, HS Mahadev Prasad, MH Amarnath (Ambarish), Roshan Baig, HK Patil, A Manju and HY Meti, RV Deshpande and DK Shivkumar are some of the prominent ministerial aspirants.
Intense lobbying is on for ministerial berths in the state which can have only 33 ministers besides the Chief Minister.
There are 60 to 70 MLAs in Congress, who have won for second and third time making it difficult for the party to choose from among them.
Siddaramaiah was chosen the Congress Legislature Party leader on Saturday after he upstaged party warhorse Union Minister Mallikarjun Kharge for the coveted post.
Shortly after his arrival here yesterday, Siddaramaiah had made it clear that people with clean image will find place in his Cabinet to be formed in a couple of days.
Parameshwara is also in the national capital.
The Chief Minister today met Prime Minister Manmohan Singh, Defence Minister A K Antony, Food Minister K V Thomas and Lok Sabha Speaker Meira Kumar.
The Chief Minister is yet to meet Congress President Sonia Gandhi.