Dushyant Chautala's Jannayak Janata Party (JJP), with the "key" as its poll symbol, was in the game to play kingmaker in Haryana as the counting of votes showed a close fight.
The BJP was ahead in 43 of Haryana's 90 assembly seats while the Congress, ahead in 26 seats, followed closely. The JJP was also ahead in 11 seats.
"I believe the keys are in the hands of the JJP," Dushyant Chautala told NDTV, adding that he saw an atmosphere of change.
"The way the trends are, it is clear that people have voted for change. The Haryana assembly will be opened with JJP keys...To think people used to call us a party of children," Mr Chautala grinned.
Dushyant Chautala is predicted by exit polls to end up with seven to 10 seats.
He remains non-committal on who he will support if Haryana ends up with a fractured verdict.
"The decision is not for Dushyant Chautala to make. There will be a national executive, a legislative party leader will be chosen...such decisions will be taken then," Mr Chautala said.
Mr Chautala, a business administration graduate from California State University, split from the INLD (Indian National Lok Dal) last year after a vertical split in the party and the Chautala family.
Dushyant Chautala's father Ajay Chautala, is the older son of four-time Chief Minister and INLD President Om Prakash Chautala.
The INLD, which last ruled Haryana from 2000 to 2004, and was the main opposition party in the outgoing government, split over a feud between the brothers Ajay and Abhay Chautala. Their father remained with his younger son.
Dushyant Chautala campaigned along with his great-grandfather Devi Lal, a former Deputy Prime Minister.
The INLD relied more on its patriarch Om Prakash Chautala, who is serving a 10-year jail term in Tihar for his involvement in a teacher recruitment scam.
Dushyant Chautala fought on JJP's symbol in the Lok Sabha polls earlier this year and finished second.