AIADMK won 136 assembly seats out of 234 in 2016 assembly polls. This includes U Thaniarasu, Thameemum Ansari and S Karunas, the three independent MLAs who had won on AIADMK poll symbol. Technically, they are considered to be AIADMK MLAs who abide by the party whip.
Following the demise of former chief minister J Jayalaliathaa and the rebel leader TTV Dhinakaran winning the bypoll in the RK Nagar constituency, the party's strength fell to 135.
Again, the demise of the Thiruparankundram AIADMK legislator AK Bose brought the tally further down to 134.
Today's HC verdict upholding the disqualification of the 18 MLAs brought the tally down furhter to 116, in a house of 214.
Subtracting the Speaker, the party's strength is 115.
Out of 115, 109 MLAs are strongly backing the Chief Minister Edappadi K Palaniswami. Three of the party MLAs are openly supporting the rebel leader TTV Dhinakaran.
Out of the three independent candidates, two are undecided in their stance. The other one, Karunas, has been vocally opposing the regime.
So, if there is a floor test, the simple majority in the house of 214 is 108. Palaniswami is expected to have the backing of 109 MLAs and will comfortably sail through the floor test. The remaining six MLAs may also face disqualification if they vote against the ruling party.
But in case of a by-poll for the 20 vacant seats, the ruling party will have to win at least 9 seats to reach get a simple majority of 118 in a house of 234.
The principal opposition DMK and its allies have a total of 97 MLAs, one down from its actual strength of 98 due to the demise of its leader M Karunanidhi. Even if the party hopes to win all the 20 seats in the bypolls, it can get only to 117 in a house of 234 and one short of a simple majority.