Campaigners for a "no" vote in the "smacking" referendum have split over what should happen next after what is expected to be an overwhelming victory.

Polls have shown more than 80 per cent of voters planning to vote "no" to the referendum question, "Should a smack as part of good parental correction be a criminal offence in New Zealand?". Voting in the three-week referendum ends tomorrow.

Green MP Sue Bradford's 2007 law, which banned the use of parental force for correction, required a review of the law "as soon as practicable" after two years. The two years expired in June so the issue is due to come back to Parliament soon.

But the two most prominent leaders of the campaign to change the law disagree about how to change it.

Family First director Bob McCoskrie, who manages the Vote No website, supports a private member's bill proposed by Act MP John Boscawen to allow the use of force for correction only if it did not cause more than "transitory and trifling" injury, did not use any weapon or instrument and was not "cruel or degrading".

"It's important that people understand that the referendum is only stage one. Stage two is getting the law changed," he said. "Stage three is targeting the real issues of child abuse. So we've got a long way to go. We're just warming up."

The Boscawen bill largely repeats amendments to Ms Bradford's bill proposed by National MP Chester Borrows in February 2007.

But Kiwi Party leader Larry Baldock, who organised the petitions which forced the referendum, said he did not think there was any chance the National Government would go back to that proposal. "I don't think the Prime Minister or the public really have the appetite for another round of that scheme or a new law," he said.

He proposes simply deleting two clauses in the Bradford law - the key clause banning the use of force for correction, and another stating that the ban on correction prevails over a clause permitting force to prevent harmful, criminal, disruptive or offensive behaviour and to perform "the normal daily tasks that are incidental to good care and parenting".

Mr Baldock said his proposal, unlike the Boscawen bill, would let parents hit their children with instruments such as a wooden spoon.

"I'm not opposed to the wooden spoon or ruler because you can control things with that better than you can with an open hand."