She will be up against Cabinet Minister Simon Bridges in Tauranga, who won in 2014 with a majority of nearly 15,000 votes. But ranked at 14 on Labour's list, she is all but certain to get into Parliament.
Tinetti is Labour through-and-through. She was born in mining country on the West Coast, and later became a primary school teacher and unionist. She admits to "wavering" in her political loyalty once in the 1980s, when she voted for Alliance in protest at Labour's Rogernomics reforms.
She has been a principal for 20 years, firstly in Southland and for the last 11 years at Merivale. It is Tauranga's only Decile 1 school and its small roll of 150 students is predominantly Maori. Many of the students have been expelled from other schools.
"It's a special place because we offer them an environment which they're able to succeed in," Tinetti said. "And that doesn't always mean academic success, it might just be coming to school every day."
The school had been affected by major reforms of the education sector, she said. It followed the Maori curriculum and had a "flexible" approach to teaching because of its high-needs students.
The reporting requirements demanded by National Standards had "narrowed what we are able to do", she said.
Her school had also been affected by underfunding, she said. The number of teacher aides, who worked with special needs students, had fallen from 10 to four.
"I'm constantly having to make cutbacks, to the point that I just struggle on what exactly I can cut back on.
"The biggest detriment to our children is that we're unable to employ the personnel any longer."
She said she had tried to remain apolitical in her principal role. But she found it increasingly difficult when poorer households in Tauranga began struggling to get into housing. During winter, up to 10 per cent of her students were homeless.
"I was starting to see things becoming more desperate for families," she said.
After speaking out about it, she was approached by Labour to run for Parliament.
Tinetti is part of a relatively strong lineup of women candidates for Labour this year.
Maungakiekie candidate Priyanca Radhakrishnan, who previously worked at Shakti, a women's refuge for immigrants, is ranked at 11 and is also set to become an MP.
Northland-based Willow-Jean Prime is ranked at 16 and is the party's highest-placed Maori candidate.
East Coast candidate Kiri Allan, Hutt South candidate Ginny Andersen, and Rangitata candidate Jo Luxton have also been given winnable places on the list.
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