Country Labor has called on the NSW Electoral Commission to investigate an allegedly illegal letter distributed in the seat of Upper Hunter on behalf of Nationals candidate Michael Johnsen.
The letter sparked a last minute controversy in one of the state's most marginal seats on the eve of Saturday's election.
The March 18 letter appears on Mr Johnsen's letterhead and bears his signature, but was sent from the party's head office.
Titled 'Labor to tax senior's savings', it states: "Hundreds of thousands of people will lose up to 30 per cent of their income because of Labor's retiree tax, taking money that would otherwise be spent by seniors and their families"
Labor has reported the letter to the NSW Electoral Commission on the basis that it was not approved by the commission.
But a National Party spokesman argued the letter was completely legal.
"The NSW Electoral Commission has no role in approving electoral material sent to constituents. We have ensured the letter complies with the Electoral Act," he said.
A commission spokesman said it did not confirm or comment on complaints and investigations.
Labor candidate Melanie Dagg accused Mr Johnsen of attempting to campaign on federal issues because he was unwilling or unable to defend State Government policies.
"Michael Johnsen and the Nationals resort to these deceptive tactics because they cannot defend their own record in the Upper Hunter, they cannot defend their own State Government policy to lavish billions on Sydney stadiums, and unlike Country Labor, they have nothing positive to offer voters in this election," Ms Dagg said.
"They have no positive plan for schools, hospitals and jobs in the Upper Hunter, so Michael Johnsen and the Nationals are scrambling in a desperate, final hours attempt to mislead voters."
The Upper Hunter seat, held by Mr Johnsen with a margin of 2.2 per cent, is likely to go down to the wire.
Federal Resources Minister Matt Canavan visited Mr Johnsen on the campaign trail on Friday to discuss what they described as "emerging risks to the state's resources sector."
It follows a visit to the seat by another high profile National, Barnaby Joyce, a week ago.
The New England MP joined Mr Johnsen in reaffirming their commitment to the mining sector.
"I'm prepared to stand up and fight for the residents of Singleton and Muswellbrook because they need jobs and incomes," Mr Joyce said.
"And, the coal industry does just that and will continue to provide jobs and good incomes.