TRS candidate Bhupal Reddy polled 93,076 votes, while Congress's P Sanjeeva Reddy secured 39,451 votes and the TDP nominee Vijaypal Reddy, brother of Bhupal Reddy, got only 14,787 votes.
The by-poll in the segment, considered a Congress bastion, was necessitated due to the death Sanjeeva Reddy's father P Kishta Reddy.
Thanking people, TRS supremo and Telangana Chief Minister K Chandrasekhar Rao said,"..I convey my gratitude to the people of Narayankhed who scripted a new history".
The party also had secured a landslide win in the Greater Hyderabad Municipal Corporation polls, by bagging 99 seats in the 150-member civic body.
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"The victory in the by-poll is a birthday gift to the Chief Minister", said Irrigation Minister T Harish Rao, who led the party campaign in Narayankhed.
Harish Rao, KCR's nephew, promised to initiate steps for faster development of the Narayanakhed assembly constituency.
Bhupal Reddy also thanked the voters and promised to fulfil the promises made to them.