Later, Muthalik told reporters, that he had joined the BJP to ensure that Narendra Modi becomes the country's next Prime Minister.
BJP leaders also felt that his entry would benefit the BJP in other parts of the Dharwad district as well as neighbouring districts.
He has had a love-hate relation with the BJP, since the saffron party had accused him of misusing Modi's name to raise funds.
He joined the RSS in 1975 and the Shiv Sena in 2005, but left the latter in 2006.
This is the first time he was officially being associated with the BJP.