Tensions within the coalition are boiling over in the tightly contested Victorian seat of Murray, with the Nationals concerned the Liberals are handing out how-to-vote cards for Labor.
The junior coalition partner is incensed after Liberal candidate Duncan McGauchie was snapped on Friday holding the Labor leaflets outside a polling booth.
Mr McGauchie is facing a strong challenge from Nationals candidate Damian Drum for the seat, which has been in Liberal hands for two decades.
Labor is preferencing the Liberals in the seat.
Nationals leader Barnaby Joyce says it's for the Liberal party to answer if they have been handing out for Labor.
"It's a hard-run campaign there and strange things happen in hard-run campaigns," he told AAP.
Nationals Victorian director Sally Branson says conservative voters would be shocked at the tactic.
"It just shows the extent some people will go to, to get a job in Canberra," she told AAP.
"It's disappointing these conversations take away from what really matters for the people of Murray."
But a spokesman for Mr McGauchie said he wasn't handing out Labor cards but holding it from someone who had just cast their vote.
"He was returning it to the Labor party volunteers who were recycling it," spokesman Paul Price told AAP.
However, Mr Price in turn accused Nationals senator Bridget McKenzie of handing out how-to-vote cards in the past week for the Greens, who've put the Nationals ahead of the Liberals in Murray.
"To make a fuss about Duncan receiving a recycled how to vote card ... is a bit rough given the Nats have been handing out for the Greens."