The appointment of Mr Joshi, representing Dharwad, was announced by Karnataka BJP just a day after the Election Commission declared the poll schedule.
Mr Joshi pipped other contenders as he has a comparatively wider appeal and hails from north Karnataka which the party considers as stronghold but where it is facing a threat to its prospects from former BJP strongman B S Yeddyurappa.
Numerically powerful Lingayat community to which Yeddyurappa belongs has a strong presence in north Karnataka.
A second time Lok Sabha member from Dharwad, from where Chief Minister Jagadish Shettar also hails, 50-year-old Joshi, eclipsed former Chief Minister D V Sadananda Gowda, Mangalore Lok Sabha member Nalin Kumar Kateel and Minister Govind M Karjol who were also in the race.
Senior BJP leader Arun Jaitley and the party's in-charge of Karnataka affairs Dharmendra Pradhan were in the city recently eliciting the views of key players in the party's state unit on a successor to K S Eshwarappa who resigned from the post earlier this month.
Some BJP leaders also saw the "imprint" of senior party leader H N Anant Kumar in the selection of Joshi whose case he has reportedly taken up after Mr Karjol fell out of the race.
Mr Joshi has his task cut out, with just under seven weeks to go for polls. Anti-incumbency factor is weighing heavily on BJP leaders even as Yeddyurappa, who has formed Karnataka Janatha Paksha, is hell-bent on spoiling its party.
Reacting to Joshi's appointment, Yeddyurappa said it wasn't a surprise to him as Anant Kumar, his bete noire, has been persisting with his name. "Anant Kumar is afraid to head the sinking BJP ship and hence he has suggested Joshi's name."
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