Former Prime Minister Sir John Key says he offered to endorse National in a video, urging Kiwis to vote blue and avoid uncertainty.

It was released on the Party's social media channels today.

He says it aimed to address complacency in the electorate.

"There's quite a bit of complacency in the electorate. A lot of people are saying National's going to win- look at the TAB odds, for instance- the problem with all that is, that would be great if there was predictability."

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