In the heartland Labour territory of South Auckland this morning, Goff got a warm reception at the Otahuhu market.
A small Grey Power audience gathered at the Wesley Methodist Church to hear him speak this morning.
"People at the top have got a lot of money and they take their holidays in Hawaii," Goff said.
"People at the bottom can't even afford to put good food on the table for their kids."
Key, a multi-millionaire, regularly holidays with his family at a home he owns in Hawaii.
"Everybody deserves to have a living wage, that's what New Zealand is about. We don't think you can live on $13 an hour so we're going to do something about it," Goff said.
"When you boost the minimum wage for people that have got very little to spend, you create demand for goods and services. These aren't people holidaying overseas or bringing in Lamborghinis. These are people that will buy the basic things because that's what their families need."
A Fairfax Media-Research International poll released this morning showed more people felt Key would lie than those that thought Goff would.
The poll was carried out after Goff controversially said in a televised debate with Key that he had lied about an increase in GST.
Key responded at the time by saying he would not call Goff a liar because he respected the office of the opposition leader, although he then went on to charge that Goff was "intellectually dishonest" about his party's costings.
Asked this morning about today's new poll, Goff said: "You can't go around promising things and then breaking your word. He [Key] promised that GST would not be going up - he broke his word.
"Clearly, he promised the people of New Zealand that he wouldn't increase the GST - he did. What do you call that?"
Goff, like his Labour counterparts, was again today pressing the asset sales issue.
National Party insiders have privately admitted there is significant opposition to their partial assets sales proposal and Labour has in the last few days honed in on the issue as it tries to rally support before election day.
Goff said it was "a bloody rip off" that foreign banks would net $100 million out of brokering the sales.
"They're paying $100m to line the pockets of Aussie banks - that's money that we should be keeping in New Zealand," he said.
"New Zealanders have got 16 days to make a decision. If you want to sell the assets off, vote for John Key. If you want to keep our New Zealand assets here in New Zealand, vote for Labour and Phil Goff."
Key has repeatedly charged that the "mixed ownership model" National is proposing would see majority share-holding stay with the Government.
Air New Zealand already operates under that model and Key has challenged Goff on why Labour would not buy out all of the privately held shares in the airline.
But Goff today said the mixed ownership model tag was "weasel words".
"We're not going to nationalise shares that we don't own at the moment. We bought back the shares we needed to get Air New Zealand going," he said.
Asked if Air New Zealand's success was evidence that the mixed ownership model could work in other cases, Goff said: "I know this. It didn't go well under a privatised model, it went bankrupt and it took a Labour Government to buy it back."