"If I turn up, you say I'm desperate to win. If you don't turn up, you say I'm ignoring the Far North. When we announce policies on infrastructure you say we're trying to bribe people, and if we don't you say we don't care. That's politics."
The ten bridges policy was derided as 'pork barrel' - an attempt to persuade voters by throwing money at the byelection.
In the 3News Reid Research Poll this week, about three quarters of voters agreed it was a bribe. Mr Key said there would be 'promises' around New Zealand, including Northland.
Some would be in the Budget in May.
Mr Key defended the bridges announcement, saying if National had not made any concrete promises, it would have been criticised for taking the electorate for granted.
He said New Zealand First leader Winston Peters had made a raft of promises, from ports and rail to free ferry travel for Super GoldCard holders, "none of which he'll ever complete".
However, he had not faced the same scrutiny. "So it's ok for him to campaign, but we should campaign with one hand behind our backs? You can't have it both ways."
Two polls this week put NZ First leader Winston Peters between 15 and 20 percentage points ahead of National's Mark Osborne.
Mr Key was in Paihia and Kerikeri today, saying his main aim was to persuade National's voters to vote.
"It's a big job but I reckon we can [turn it around]. There is a lot of latent support for National, but mobilising that support is a big issue."
He said the poll gap was on local issues, rather than a vote of no confidence in National.
He did not believe National had let down the people of Northland, but said more could be done and the discontent was a result of "decades and decades" of Northland being behind Auckland.
Mr Peters' campaign has been based on "sending them a message" and Mr Key said National had heard that message.
"The people of Northland are ambitious and want Northland to do better. We hear that message loud and clear. We are not naive about it, we have to share resources right around the country - it can't just solely be about Northland."
He believed National had done a good job of lifting the economy, he said, but more was needed.
Highlights of a visit to Paihia
Sledging with an Australian and a Mexican standoff were highlights of a visit to Paihia by Prime Minister John Key and Mark Osborne this morning as the pair launched into the last day of campaigning.
While New Zealand First leader Winston Peters was on one last joyride from Kaitaia down the electorate, National was in Paihia where it got a warmer welcome than Dargaville yesterday.
The most entertaining exchange was an Australian tourist, who later admitted he mistook Mr Osborne for the Prime Minister.
He posed for a photo with Mr Key and then the pair engaged in mutual sledging over Sunday night's Cricket World Cup final. After Key told him New Zealand would win, the Australian replied: "You can keep dreaming."
Mr Key pointed to a shop down the street: "Just down there you can buy a nice hanky to wipe away your tears on Sunday evening."
Mr Key also ran into a Mexican man who said he was a great fan, but had not lived in New Zealand long enough to vote.
Mr Key and Mr Osborne also ran into National supporters, Rhonda Blakie and Ruth Butcher who told him they had voted for Mr Osborne.
"We've voted in the right way - don't know if it will do any good."
Asked later what they thought of Mr Peters, they said he had done a lot for older people in Auckland "but nothing for anyone up here".
A relief teacher asked why he should vote for Mr Osborne over Mr Peters and Mr Osborne replied that he was a local, and in the governing party which meant he had influence to push things through.
Speaking to workers at a kiwifruit packing shed in Kerikeri later, Mr Key and Mr Osborne again both emphasised his local base. Mr Osborne spoke of marrying his wife in Kerikeri and playing rugby locally, as well as his role on his children's school board.
In a clear reference to Mr Peters' living in Auckland, Mr Osborne said: "We need someone who makes the case for issues every day, not someone you hear from for four weeks during a campaign and then you never hear from again."
