Nobody in the Thackeray family has ever contested an election or held any government post.
"People have a lot of love for and expectations from our party. If the mandate is for MNS, I will not hesitate to lead it," he said.
The MNS, which had declared support to Narendra Modi for the Prime Minister's post and fielded just nine candidates, mostly against Shiv Sena, in Lok Sabha polls, had suffered a wash-out. Many of its candidates even lost their deposits.
The MNS had earlier announced that Raj Thackeray would be its chief ministerial candidate.
Addressing his first rally in Mumbai on Saturday after Lok Sabha poll rout, Raj said he would bounce back in coming assembly elections.
"Political pundits said I am finished... but look at the crowd gathered here... does the rally have a look of a defeated party?" he said.
He said he had seen defeats since a very young age when he was in Shiv Sena. "I have learnt how to learn from defeats and bounce back."
Referring to the criticism about his party's performance so far, Raj said "if you have expectations from me, give me time."
"In Nashik municipal corporation, it was just about two years ago that my party came to power. You don't question those who are ruling the civic bodies for more than 30 years... how can I fulfil all the promises in two years," he said.
Raj's uncle Bal Thackeray founded Shiv Sena in 1960s and led it to power in the state assembly elections in alliance with BJP in 1995 but he himself never contested an election, or took up any post in the government.
Referring to the party's agitation against toll collection on state roads which was dubbed as a flop-show by many in the media, Raj said "isn't it enough that due to the agitation, 65 toll booths in the state were shut down?"
Describing the Lok Sabha polls' outcome as a verdict "only" for Narendra Modi, Raj said he had sensed the mood of the people and knew NDA would cross 300 seats.
Raj claimed he did not want to contest Lok Sabha elections.
"However, some people in my party felt otherwise, and after my meeting with (senior BJP leader) Nitin Gadkari, I decided to contest," he said.
"Everybody in BJP and among its allies who have won owe it to Narendra Modi. Even my friends in BJP were surprised by the result," Raj said.
Talking about MNS's rout despite his announcement of support for Modi, Raj said people heeded only Modi's appeal.
"Modi appealed for votes for BJP and its allies," he said, insinuating that Shiv Sena (from which Raj broke away a few years ago) essentially piggybacked on the support for Modi.
Taking a jibe at Congress vice president Rahul Gandhi, Raj said "Rahul is the true follower of Mahatma Gandhi. He is now fulfilling the Mahatma's wish of dissolving the Congress after the independence."
Raj congratulated Modi on becoming the Prime Minister. "It is good that there is a now a single party government (with BJP having majority on its own) and there is no need for anybody's crutches," he said.
Taking his partymen to task, Raj also said some leaders did not work for the party candidates and he would deal with them in due course.
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