Maithreyan, chief of AIADMK's medical wing, is one of the six MPs from the state whose term expires by July 27. The others are AIADMK's A Elavarasan, Kanimozhi and Tiruchi N Siva (both DMK), B S Gnanadesikan (Congress) and CPI's D Raja.
According to party release, the other four nominees announced by Jayalalithaa are -- K R Arjunan, T Rathinavel, Dr R Lakshmanan and S Saravanaperumal.
Of the five AIADMK candidates, the ruling party is assured of netting four seats on its own by virtue of its 151-member strength in Tamil Nadu assembly, whose total strength is 234.
Thirty four first preference votes are required for a candidate to be declared elected.
The Jayalalithaa-led party is likely to woo legislators from other parties, including six dissident DMDK MLAs besides smaller allies like MMK and Puthiya Tamizhagam to win the fifth seat.
AIADMK may also woo CPI (eight MLAs), as the two have been on good terms inside and outside the assembly.
Jayalalithaa not nominating a member for the sixth vacancy has opened up an interesting set of calculations.
Speculations are already rife that main opposition DMDK with 29 members (including the six dissidents) and DMK (23 MLAs) could go in for a consensus candidate though neither of them have announced any decision so far.
Congress has five MLAs while PMK has three.
Meanwhile, top CPI leaders, A B Bardhan and Sudhakar Reddy, today met J Jayalalithaa in New Delhi to seek support of the ruling party in Tamil Nadu for its Rajya Sabha candidate.
"She told us she has declared (her candidates for) five seats and hopes to win those five. She wished us well for the elections," Bardhan told reporters after a 30-minute meeting he and the CPI general secretary had with the Tamil Nadu chief minister.
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