The Tukituki electorate, named after the river that runs through it, has regularly swung between Labour and National over the years, and the jury is out on where the pendulum will fall in this year's election.
Created just before MMP voting was introduced in the 1996 election, the electorate arose from the old Hastings being merged with northern areas of Central Hawke's Bay.
In 2007 there was a southern boundary shift south to Pourerere and the northern boundary extended to include Te Awanga and Cape Kidnappers.
Labour's Rick Barker, who had represented Hastings since 1993, was elected as MP for the new Tukituki electorate in 1996, until a large shift to the National Party in 2005 saw Craig Foss claim the seat.
This year pundits are picking a close race between National candidate Lawrence Yule and Labour candidate Anna Lorck, with many factors coming into play in determining their success or failure.
Former Labour Party president Mike Williams said Tukituki had long been considered a bellwether electorate - where Hastings went the government would go.
He ran his first-ever election campaign in Tukituki in 1978 when the Hastings seat comprised Hastings and Havelock North, but not Flaxmere, and the boundary favoured National.
At that time David Butcher was the Labour candidate and Bob Fenton was the National candidate. Mr Fenton, a Springbok tour supporter, had started an organisation he called WARD - War on Recreational Disruption, Mr Williams said.
"It was very interesting - Jeremy Dwyer was Social Credit and later became mayor of Hastings - Butcher won the seat and Dwyer got a whole lot of votes in Havelock North."
Despite Mr Butcher winning, however, in a close-run race that saw the votes recounted, the National Party, led by Robert Muldoon, retained office, although the Labour Party managed to win the largest share of the vote.
Mr Williams said Tukituki was very much in play this election, despite former National MP Craig Foss' healthy 6490-vote lead in 2014.
"That's quite hard to overturn but we have a swing towards Labour showing in the polls and that will be reflected in the electorate - Anna is on her second time round, has matured, and has a bigger organisation behind her.
"But Yule presided over the Havelock North poisoned water scandal and no one has taken responsibility.
"If I was a betting man I would say the vote in Havelock North will be nothing like what Foss got last time."
Hawke's Bay based political strategist and campaign manager Simon Lusk said when Mr Barker won in 1993 he benefited from being the incumbent in the old Hastings seat, coupled with a strong swing against the National Government.
"Barker was an effective local MP, and there were further swings against the Government in 1996 and 1999 when the Tukituki electorate had expanded to take in rural areas and Waipukurau and Waipawa.
"In 2002 National's appalling campaign meant Barker won again by a handsome majority."
This changed in 2005, with Don Brash's Orewa speech resonating with provincial New Zealand. National won 10 seats from Labour that year, including Tukituki, Napier and Wairarapa, he said.
"Mr Barker's ability to be a good local MP had been hampered by becoming a Cabinet minister and having to spend more time in Wellington and around the country as a minister."
Mr Foss held Tukituki with a strong National campaign in 2008, and again in 2011 and 2014.
"His retirement means that Tukituki is an open race - there is no power of incumbency."
Mr Lusk said open races were considered easier to win for opposing parties than running against an incumbent, but National replaced Mr Foss with Mr Yule, who had a very high profile and very high name recognition.
"Tukituki remains a swing seat and one Labour almost certainly has to win back if it wants to form a government.
"Of the four seats in our region Tukituki is the most likely to swing, though this will largely depend on the campaigns by Labour and National across the country, which is more important than the local campaigns."