The open letter calls on them to make regional passenger rail a priority and a commitment to deliver on this priority after the election.
It has already been signed by various representatives of 16 New Zealand councils and local boards, including the Otago Regional Council and Dunedin City Council.
Horizons regional councillor Sam Ferguson, who penned the letter, said the issue had been building momentum.
"When we look at what we’re trying to achieve in communities with shifting modes of transport, we note that without that spine of rail, it would be difficult to achieve that shift at all."
Mr Ferguson said he had been inspired by public meetings where people had advocated for passenger rail, particularly as the climate crisis takes effect.
There was an opportunity to raise the issue in an election year, he said, particularly with so much of the focus being on new roads.
The six Dunedin city councillors who have signed the letter are Carmen Houlahan, Jim O’Malley, Kevin Gilbert, Mandy Mayhem, Sophie Barker and Steve Walker.
Dunedin Mayor Jules Radich said he had not seen the letter, but he was "enthusiastic" about the prospect for passenger rail.
Otago regional councillor Elliot Weir said under-investment in rail by past governments had forced more cars and freight on to New Zealand roads.
"We need to reduce our transport emissions, and regional rail is one of our best options."
Dunedin deputy mayor Sophie Barker said the timing was right, especially for the city.
"Anything that can take more cars off the road would be amazing.
Ms Barker said while a feasibility study would be likely needed, she believed passenger rail could be revived.
"More than anything else, it’s a really pleasant way to travel."
The response from the major political parties has been mixed.
Labour Party MP for Taieri Ingrid Leary said "once we can get freight rail going, then we can look at options for passenger rail".
"I would love to see passenger rail.
"However, I’m a pragmatist, and so I’m looking at the most practical pathway in the medium term," Ms Leary said.
Act New Zealand party leader David Seymour said it was not viable.
"We’re committed to roads people actually use, rather than social engineering and uneconomic modes of travel," Mr Seymour said.
Green Party transport spokeswoman Julie Anne Genter said the party stood "alongside the councillors across the motu calling for political parties to commit to supporting regional rail".
National Party transport spokesman Simeon Brown said the party would only support regional rail in areas where it "stacked up" economically and socially.
