There are six seats on offer and election becomes necessary only if a seventh candidate enters the fray.
Congress MPs T Subbirami Reddy, K V P Ramachandra Rao, Nandi Yellaiah, T Ratna Bai and M A Khan are set to retire in April, but the Congress is not sure to win at least four seats now.
The ruling party has 146 MLAs in the AP Assembly and it may be in a comfortable position to bag three seats.
Even among the 146, at least 30 Congress MLAs have been waiting for the opportune time to cross over to other parties, protesting the move to bifurcate the state.
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A lot of political changes are expected after January 23 and the eventual scenario will largely influence the outcome of the Rajya Sabha election, observers say.
If YSR Congress, which claims to have a strength of 23 MLAs, chooses to field its candidate, the Congress' woes will only compound as many fence-sitters from Seemandhra region may throw their weight behind the former.
"This will also help us prove our growing strength," a senior YSRC leader said.
But the party is expected to finalise its strategy after the conclusion of the winter session of the state legislature.
Another predominant group within the Congress is set to switch over to the Telugu Desam Party, thereby further reducing the ruling party's numbers in the 294-member House that now has an effective strength of 279 due to disqualification of 15 members.
The party hopes to muster support from TRS that has 17 MLAs besides two associates.
The TDP, whose Rajya Sabha member Nandamuri Harikrishna resigned late last year, is set to win two seats in the biennial election, given its strength of 80 in the House.