DK Shivakumar is set to lead the revamped Karnataka cabinet, with two deputy chief ministers and a key role for Siddaramaiah's son Yathindra.
The Congress legislature party is expected to elect Shivakumar as its leader at a meeting on Saturday, paving the way for his swearing-in as chief minister on June 3.
Satish Jarkiholi has been offered the post of deputy CM, but there is no word on his acceptance yet.
Siddaramaiah's son Yathindra is likely to be inducted as a cabinet minister, with a politically significant role in the social welfare department.
However, leaders aligned with Shivakumar have opposed Siddaramaiah's proposal for a broader coordination mechanism linking the Congress organisation and the state government.