Of the 34 results declared so far, the main opposition Mizo National Front lagged far behind, bagging only three seats, the same number it had won in 2008.
Four-time Chief Minister Lal Thanhawla won from both Serchhip and Hrangturzo seats he had contested.
In Serchhip, he won by a margin of 734 votes, defeating his nearest MNF rival Lalramzauva, who got 4,985 votes in a four-cornered contest.
In Hrangturzo, the chief minister defeated his Mizoram People's Conference rival Lalthansanga by 1,638 votes. Thanhawla received 5173 votes in a five-cornered contest.
Of the eleven ministers who contested, eight -- R Lalzirliana (home), J H. Rothuama (cooperation), P C Zoram Sangliana (transport), H. Rohluna (forests), Lalrinliana Sailo
(health), Lalsawta (education), Zodintluanga (sports) and P C Lalthanliana (social welfare) -- won.
Assembly Speaker Romawia won from the prestigious Aizawl North-I seat.
Tourism Minister S Hiato, however, lost to the MNF's K Beichhua in Saiha.
Congress also bagged the Tuivawl, South Tuipui, Lunglei South, Palak, Champhai North, Lawngtlai West, Tuirial, Tawi and Tuichawng seats.
On the poll outcome, Lal Thanhawla said contrary to anti-incumbency playing a crucial role after completion of a five-year term, in Mizoram "pro-incumbency worked in favour of the Congress".
"I am going to form the next government in the state," he said.
The opposition MNF bagged the Saiha, Tuikum and Lawngtlai East seats.
Barring MNF, the two other constituents -- the MPC and Maraland Democratic Front -- of the Mizoram Democratic Alliance were yet to open their account.
A prominent loser was opposition Zoram Nationalist Party chief Lalduhawma, who lost both from Aizawl West-I and Kolasib. The party had two seats in the outgoing House.
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