The electorate comprises the northern parts of Tawa, Porirua Harbour communities, and Kāpiti Coast towns including Pukerua Bay and Raumati Beach.
National's Jo Hayes is running against Edmonds. She's ranked 44 on the party list so, based on current polling, won't be back into Parliament unless she wins the electorate.
But Mana is a pretty safe seat for Labour- it has never been held by any other party.
Current MP Kris Faafoi secured a 10,980 majority over National's candidate in 2017.
Faafoi is running list-only this election, which left the door open for a new candidate.
Edmonds was at home on the weekend when a live-feed of Faafoi's announcement popped up on her Facebook page.
That day she received several messages and phone calls about running.
"It was a pretty firm no at that time if I'm really frank with you," she says.
Working as a ministerial adviser, she had seen first-hand how hard it could be for politicians to strike a work life balance.
Edmonds is a lawyer and mother of eight and was concerned about how such a move might affect her family.
But after talking with a mentor, and with her husband's support firmly behind her, she decided to put her hand up.
She says she's found a lot support of for Prime Minister Jacinda Ardern's leadership out on the campaign, but has also discovered a nasty underbelly of racism too.
Edmonds says one person told her they would party vote Labour but not for her because they didn't like the Black Lives Matter protests.
She says she's also watched people end conversations with her volunteers as soon as they find out she's Samoan.
"People think now I'm a politician they are entitled to tell me exactly how they feel and be quite open about not liking me because I'm a Samoan woman."
Edmonds says it's off-putting, but also reminds her why she's standing, so that young Samoan girls can see her stepping up and think "I can be like her".
Mana wasn't the first choice for Hayes, who has been a list MP for the past six years.
She tried in Palmerston North to begin with this election, but National selected 17-year-old newcomer William Wood instead.
Hayes first stood in Dunedin South in 2011 but has never found a political home.
She sought selection in Wairarapa in 2014 but was beaten by Alistair Scott who won the right to stand for National.
Hayes was directed towards the safe Labour seat of Christchurch East and stood there in 2014 and 2017.
"As a listy they [the party] basically shunted me where they needed me, so that's why I ended up in the deep red seats down south," she says.
Asked why she has missed out on being selected closer to Rangitikei, where her family is from, she says: "I don't know, your guess is as good as mine."
Hayes recalls being interviewed by a journalist in Dunedin who told her people might say she's a carpetbagger.
"I said we're all carpetbaggers, mate."
Hayes sees her political history as an advantage because she has seen a lot, spoken to many people, and is an experienced sitting MP.
She thinks she can claw back some of the National's Party vote in the electorate.
National has actually been ahead in the party vote in recent times until Faafoi managed to swing it in 2017.
The seat even came close to turning blue in 2011 with Faafoi securing just a 2230 majority over National's Hekia Parata.
She says the big issues facing the electorate are three waters infrastructure in Porirua, coastal erosion, and housing.
Hayes said Porirua City Council had missed out on funding for horizontal infrastructure through the Government's shovel ready scheme.
She says a helping hand would come in the form of National's promise to create a single Crown-owned bank to streamline financing for infrastructure projects in both central and local governments.
"It might not be the whole end, but it's better than getting nothing from a shovel ready project," Hayes says.
Edmonds says three waters reform has already started under a Labour-led Government, noting local councils have signed up to an MOU on the first stage of the programme unlocking millions of dollars.
Both agree housing is a big issue.
Hayes stresses no Government can solve the housing crisis in one term, but that it's crucial to continue making inroads to the shortage with renewal and replacement.
Edmonds says she wants to build on the Progressive Home Ownership scheme that's under way and make sure the $1.5 billion regeneration project in Porirua East doesn't result in unaffordable developments.
Hayes wants to see a better partnership between local and central government on work around coastal erosion.
Edmonds says she's been trying to explain to people the connection between climate change and the cost of living, like insurance premiums for example.
Both candidates were asked to explain why people should vote for them in one sentence.
Hayes says: "I bring experience not just politically but work experience as well. I know what it is to run a business, I come with a link to community and know what communities expect from somebody like me. I also bring a no nonsense attitude to get things done for you."
Edmonds says: "I have a unique set of skills- I've worked in the public sector, in the private sector in the community sector. I live in this community, I'm from this community, so I think I'll be the best voice for this community."
Both had a bit of leeway with the "one sentence" requirement.
Green Party candidate Jan Logie has lived in the electorate for more than a decade and has a home in Cannons Creek.
She believes the party's solutions will be particularly beneficial to communities in Mana.
"We have an extended coastline and low lying areas that are feeling the impacts already of climate change. People really are calling for us to act faster and put more policies in place to protect against climate change."
Logie said inequality was felt and seen in Mana and the Greens' guaranteed basic income would help communities to thrive.
"Quite often I hear people arguing against climate action because they don't think people on low incomes will be able to afford policies, so that's about ensuring that people have got guaranteed minimum incomes to be able to withstand any increase in costs."
Integrity Party leader Helen Cartwright is standing in Mana where she has lived for the past 16 years.
The party's main concern first and foremost is waste minimisation, but Cartwright is also keenly aware of the huge income disparity in the electorate.
"If you look at the two sides of the Cannons Creek hill or the two sides of Transmission Gully, one side is wealthy and affluent and the other side is on its knees and we need to do something about that."
Michael Walker is standing for the Progressive Party.
He says people in Mana will be exposed to national issues like the Covid-19 economic recovery and climate change.
Walker says the party has a holistic approach to policy by looking at people through a mental and spiritual lens, as well as physical.