Eden-Monaro byelection Labor candidate Kristy McBain has mistakenly pledged to represent Wagga, a city about 65 kilometres outside the seat she is trying to win.
In a newspaper advertisement published in The Daily Advertiser on Thursday, Ms McBain's campaign used the slogan "I'll be a local voice for Wagga Wagga".
Wagga and its suburbs sit entirely within the Riverina federal electorate, which has been held by Nationals MP Michael McCormack since 2010, and have never been part of Eden-Monaro.
Mr McCormack said the Labor party's Sydney head office should "take a close look at a map of the electorate it is seeking to represent".
"If you don't even know which towns you're seeking to represent, you cannot be an effective advocate for your community," he said.
A spokesperson for Ms McBain's campaign said the advertisement's slogan was "a genuine mistake in the design process and should have said Tumut".
"Tumut, Adelong, Batlow and surrounds has a big readership of the Wagga Advertiser, just like that same area has a big audience for ABC Riverina, which is also out of Wagga," the spokesperson said.
Nationals candidate Trevor Hicks said when casting their ballot, the people of Eden-Monaro should remember which party understood their electorate and which did not.
"Whilst disappointed in Labor's lack of interest and understanding of our important electorate, I am not surprised and the people of Eden-Monaro won't be either," he said.