Tripura Chief Minister Manik Saha won the by-election from the Town Bardowali seat by a margin of 6,104 on Sunday, as per the Election Commission.
The Chief Minister, a BJP candidate, secured 17,181 votes, which is 51.63% of the total votes polled.
His nearest rival Ashish Kumar Saha of the Congress bagged 11,077 votes or 33.29% of the total votes.
The Left Front was at the third spot as Forward Bloc candidate Raghunath Sarkar secured 3,376 votes (10.15%).
"The people who voted for me, I thank them. This is the victory of BJP workers. I expected the margin to be a bit more. However, the results prove the understanding between the CPI(M) and Congress. We will work accordingly in the future, but people did not take this understanding in a good way," the Chief Minister told reporters.
"We have seen post-poll violence for many years, so we have urged the people to stay away from such a thing. People's trust is the main factor, and we have to see they don't face any problems. I would also request the opposition parties to maintain peace," he added.
Manik Saha, a Rajya Sabha MP, was appointed the Chief Minister of the State last month after then CM Biplab Deb's sudden resignation. He had to win this by-election to continue as the Chief Minister.
He will now resign as an MP after being elected to the Assembly, as per the rules.
The bypoll was held in the Town Bardowali seat after Asish Kumar Saha resigned as a BJP MLA and joined the Congress in February.
