The Greens upper house MP Cate Faehrmann is tipping a "record result" for the party in this Saturday's election.
Ms Faehrmann was in the Illawarra to meet with the region's Green MPs and talk up the party's chances.
"We are continuing to grow our vote in this area - every election we have a growing number of members and supporters," Ms Faehrmann said.
"We are looking at a two and three election strategy in the Illawarra, like we are doing in the Hunter, like we're doing in other areas. We continue to grow our vote, because at some stage we will turn the Illawarra Green."
She pointed to the 2002 election of the Greens' Michael Organ to the federal seat of Cunningham as evidence of what is possible.
"We will do better in this election than we have at any other state election in NSW."
Ms Faehrmann said the possibility of a close election was a good sign for the Greens.
"We do know that in this election we have a very good chance of being able to be in the balance of power and get some outcome on some key issues for us," she said.
"Polls are predicted to be very tight. We have said we will never support a Liberal-National government, but we have also said to Labor, don't take our support for granted."
Two weeks ago the party released a list of seven issues Labor would have to take action on to win the support of the Greens.
These included scrapping the public sector wage cap, introducing a mandatory cashless gambling card and a commitment that no new coal or gas projects are created.
"It's predicted that Labor won't get the seats that they need to govern in their own right and they will need to look at a handful of Greens and independents to be able to govern," she said.
"We have said what this is about is guaranteeing them confidence in their government so if there's someone moving no-confidence motion we would not support it so that would be able to govern confidently without instability.
"What that doesn't mean is that we are supporting everything they do by any means."