Sanganna polled 60,405 votes against 47,917 secured by Basavaraj Hitnal of Congress. Pradeep Gouda Patil JD(S) stood a distant third, getting 20,710 votes.
The polls mark the first electoral test for Chief Minister D V Sadananda Gowda after he succeeded B S Yeddyurappa in August. For the BJP, the victory is the 11th in the 18 by-elections since it came to power three years ago. Sanganna quit the JD(S) and joined the BJP, necessitating the by-poll.
The ruling party has maintained a winning streak in the by-elections despite its image being besmirched by a spate of corruption charges against senior leaders.
The mining scam led to the exit of Yeddyurappa as chief minister, after he was indicted by the Lokayukta report.
The run-up to the polls had witnessed a fight among the BJP top brass for the honour of leading the campaign.
While the Yeddyurappa camp insisted that the former chief minister lead the campaign, party State unit president Eshwarappa was adamant that Yeddyurappa stay away from the campaign, given his scam-ridden image.
Party national president Nitin Gadkari intervened to ensure that the two camps put up a joint effort.
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