Prime Minister John Key is predicting a "tight and tough" election with the Government up against a "left wing block" of parties.
Mr Key told more than 250 party faithful at a conference in Hamilton today National could not be lulled into a false sense of security by high polling numbers ahead of the September 20 general election.
He said National was not just up against the lower polling Labour but its left counterparts including the Greens, New Zealand First, and Mana.
"The real risk for us is to underestimate just how close this election will be.
"None of us should be deluded into believing that a big poll lead by National against Labour means we have election 2014 in the bag."