Although the Government has ruled out a CGT on the family home, other assets – such as farms and small businesses – could be in the taxation firing line.
For the most part, ministers have said they would not comment on any elements of tax that the working group was looking into until the report has been made public.
But yesterday, Revenue Minister Stuart Nash said he thought a CGT was about creating "fairness, balance and integrity" in the tax system.
He said he thought there was a "hole in the system at the moment", but encouraged people to wait until the final Tax Working Group report was released on Thursday.
Labour has previously campaigned on implementing a CGT. In 2011 then-leader Phil Goff wanted to introduce a 15 per cent CGT.
But the poll numbers show that even Labour supporters are divided on the issue, with 44 per cent saying they would back a government decision to implement a CGT.
But 42 per cent said they wouldn't, with the remaining 14 per cent saying they didn't know.
National Leader Simon Bridges said this should give every signal to Prime Minister Jacinda Ardern that even many of her own supporters don't back the implementing of a CGT.
He said the overall 54 per cent figure actually "felt a bit light" and added he thought more people would come to actively dislike the idea of a CGT when they work out what it means for them.
Perhaps unsurprisingly, just under three-quarters of National supporters said they would not support a CGT – 19 per cent said they would.
Tomorrow, the Tax Working Group's chairman, Sir Michael Cullen, will publically release the report.
It went before Cabinet on Monday but the Government won't be providing a full response until April.
Finance Minister Grant Robertson said any new tax policy would not come into force until April 2021, after the 2020 election.
This would give people the chance to vote on any decisions made by the Government, he said.
