On Tuesday morning, party members were gathered next to North East Valley Cricket Club grounds, beside State Highway 1, standing on a traffic island, waving signs.
Dunedin police and National Party Dunedin North candidate Michael Woodhouse dismissed the complaint as most likely politically motivated.
The complainant, Waitati resident Olive McRae, who has stood for the Dunedin City Council and has been vocal in her opposition to the fluoridation of water, said the campaigners posed a significant safety issue.
"It's not about politics. It's about the safety of it."
The spot was a high-risk crash spot, prompting her to alert the Dunedin City Council.
"They were standing ... in the middle of the road on a traffic island trying to actively divert people's attention away from driving to their election billboards."
In response, Mr Woodhouse said he accepted Ms McRae's concern might be genuine, but still thought her political background relevant.
The promotion did not pose a danger to drivers, he said.
