A overwhelming majority of voters think the major party that wins the most votes should head the incoming government, an opinion poll shows.

The One News-Colmar Brunton poll showed 79 percent of voters believed the party with the most votes should lead the next government and 47 percent say they would prefer it to be able to govern alone.

An equal number -- 47 percent -- believe the main parties should have to have a coalition partner.

On a rolling average of recent polls, National, which is well ahead of Labour would be able to govern with the support of its allies United Future and ACT.

But if the three parties lose 2-3 percent of votes, then the Maori Party will be left at the likely kingmaker opening the door to a potential Labour-led coalition.

National leader John Key told One News he believed winning the most votes would give National a "moral mandate" that all parties should "take note" of.

But Miss Clark said many voters were voting for a "community of interest" rather than a single party when they cast their vote.