Gautam, 73, defeated BJP's sitting Finance Minister Captain Abhimanyu from the Narnaud constituency in Hisar district with a margin of 12,029 votes.
His sudden outburst against Jannayak Janta Party (JJP) leader and Deputy Chief Minister Dushyant Chautala (31) is deliberate sidelining of party's legislators and taking all the plum posts.
Without mincing words, Gautam, who was also once a BJP legislator, categorically said Dushyant should not forget that he became the Deputy Chief Minister with the support of the legislators. At the same time, he clarified that he was not against the formation of the BJP-JJP government.
Sources said Gautam was the frontrunner for the cabinet berth in the Manohar Lal Khattar's first cabinet expansion in November in which 10 ministers, including one from the JJP, a lone woman and an Independent, were inducted.
"Gautam was deliberately sidelined in the new government formation owing to influence of Captain Abhimanyu, who does not want anyone from his constituency to get into the government on any crucial position," a senior BJP leader told .
He said Gautam's induction into the Cabinet was dropped at the last minute owing to reluctance of Khattar.
Interestingly, Gautam on Wednesday announced that he was resigning as party's national vice-president but not from the party.
"I am stepping down as national vice-president with immediate effect. But I will remain in the party. The situation has not come at that point that I quit the party and resign as MLA," he said.
Slamming Dushyant for keeping 11 portfolios with him, he said: "He should realise there are nine other MLAs in the party. These MLAs too were chosen by the people. Most party MLAs are disappointed over the issue."
Sources in the JJP said Gautam played a crucial role in Dushyant's victory and of other party legislators.
The saffron party's post-poll alliance partner JJP, a defector of the state's once prominent regional outfit Indian National Lok Dal (INLD), got a lone minister in Anoop Dhanak, who has been allocated less crucial Archaeology and Museums portfolios.
Both Khattar and Dushyant took oath of office on Octber 27.
Dushyant is the great grandson of former Deputy Prime Minister and the tallest Jat leader, late Devi Lal, whose INLD has been politically marginalised in the recent concluded Assembly elections in Haryana.
But INLD's off-shoot and a year old JJP, led by Dushyant Chautala, sprang a surprise by winning 10 seats in the 90-member Haryana Assembly.
In a post-electoral alliance, the JJP has extended support to the BJP, which won 40 seats, six short of the majority mark.
The Cabinet can have 14 members, including the Chief Minister and the Deputy Chief Minister, with two slots kept for future expansion.
Political observers say Gautam's outburst at this point in time may be to get a Cabinet berth.
( With inputs from IANS )