If Tailem Bend wins a round of the Supercars Championship, the first race there would likely be held in August 2018, says the series' CEO.
That possibility inched closer to reality with an allocation of $3 million over three years in Thursday's state budget.
The funding would help the Shahin family pay the necessary licensing fees as they continue their efforts to attract a second race to South Australia.
So long as all the necessary hurdles were cleared, Supercars chief executive officer James Warburton said, a Tailem Bend race could be held 14 months from now.
"A second championship event in South Australia would be absolutely outstanding given the incredible story of the Adelaide 500 over the past two decades," he said on the series' website.
"Supercars has long supported the construction of the new facility at Tailem Bend and the Shahin family in building this new circuit for all forms of motorsport.
"Subject to agreement with South Australian Tourism approval we would very much look forward to adding Tailem Bend to our 2018 racing calendar."
The operators of The Bend Motorsport Park agreed to a memorandum of understanding with the Supercars Championship in mid-2015, an in-principle agreement that a race would be held there after the circuit's completion, which was originally due this year.