"It's time to focus on the needs of the people, to make people's lives better up here," he said.
He believed there would be "real regrets" in the Mana camp about its alliance with Kim Dotcom's Internet Party, which he had suspected from the outset would work in his favour.
"I thought, 'people won't accept this'. It was (Mr Harawira's) Achilles' heel," he said.
Mr Harawira refused to concede defeat as the seat appeared to slip from his grasp, with special votes yet to be counted, but conceded on Saturday night that it was "not looking good".
On Sunday, he said his heart was at peace, however.
"I'm not one for recriminations. I just have to be better at what I do next time," he said.
He wasn't sure what the future held, but would be talking to "some folks" and would probably take a few days to think about things before making any decisions.
He did not find it easy to identify what had led to his defeat, saying the alliance with the Internet Party had been a decision made by Mana. If it worked, it worked, if it didn't, it didn't.
Meanwhile, Mike Sabin had no trouble holding Northland for National, although his final 2011 majority reduced from 11,362 to 8785, with special votes to come.
Willow-Jean Prime improved Labour's 2011 vote from 6826 to 8042, while David Clendon's Green vote fell from Pauline Evans' 3822 to 3094.
Ken Rintoul picked up 1557 votes for Focus NZ in its first election.