It was here on John Street where federal Hunter MP Joel Fitzgibbon voiced his frustration toward the current Upper Hunter MP and his tactics to retain his seat.

Country Labor called on the NSW Electoral Commission to investigate an allegedly illegal letter distributed on behalf of Mr Johnsen.

It appears on the Upper Hunter MP'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".

"It is very disappointing that Michael [Johnsen] has stooped to scaring seniors in the Upper Hunter (through his letter)," explained Mr Fitzgibbon.

"He's invoking a federal issue and he's telling lies about that issue.

"The cash rebate on dividend imputation is a plan, which would deny a tax rebate to people who don't pay any tax and 80 per cent of the $5 billion it's costing the government each year is going to the 20 per cent of top income earners in this country.

"This will not impact on Upper Hunter residents and Michael Johnsen should not be running a scare campaign and putting fear into local seniors in the Upper Hunter."

Mr Fitzgibbon believes that Country Labor candidate Melanie Dagg has what it takes to win the Upper Hunter seat on Saturday, despite after filling the void left by previous candidate Martin Rush only 44 days earlier.

"Melanie just has to keep on doing what she's doing," he explained.

"You've got the support of the miners' union and that clearly shows that Labor is the party of the mine worker and not the coalition who is pretending to be.

"She's invested in police stations, schools and hospitals and, in doing so, she's highlighted the fact that over the past four years Michael Johnsen has done nothing for his local electorate."