Wangpang Konyak of the ruling NDPP won the by-election to the Tapi assembly seat in Nagaland's Mon district on Sunday, officials said.
He defeated Congress candidate Wanglem Konyak by 5,333 votes, they said.
While the NDPP got 10,053 votes, the Congress secured 4,720 votes in the seat, they added.
The by-election was held on November 7, and recorded a turnout of 96.25 per cent.
Only two candidates fought the by-election as the Nationalist Democratic Progressive Party (NDPP) nominee was the joint candidate of the People's Democratic Alliance.
The bypoll was necessitated due to the death of NDPP MLA Noke Wangnao on August 28. Wangnao was the MLA of the constituency for the last 10 terms.
Chief Minister Neiphiu Rio, the leader of the NDPP, congratulated Wangpang Konyak.
"Heartiest congratulations to Mr. Wangpang Konyak, @NDPPofficial candidate on winning the by-election for 43-Tapi A/C. I wish him the best in serving his constituents and the people of Nagaland. I also congratulate the Party workers and well-wishers," he posted on X.
Deputy Chief Minister Y Patton of the BJP also congratulated to Wangpang Konyak, and ally NDPP for the resounding victory.
"This win demonstrates the people's faith in our alliance and the visionary leadership of CM Rio. This emphatic win has shown that the NDPP-BJP alliance truly represents the hopes and aspirations of the Naga people," he said.
In the 60-member assembly, the NDPP has 25 members, the BJP has 12, NCP has seven and the NPP has five MLAs. LJP (Ram Vilas), Naga People's Front (NPF) and RPI (Athawale) have two MLAs each, while the JD(U) has one member and there are four Independents.
All the legislators are supporting the NDPP-BJP alliance, ensuring an opposition-less government in the state for a third term.
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