A former political advisor says Jacinda Ardern handed Judith Collins the victory at last night's TV debate.

Jacinda Ardern wouldn't pick a winner but Judith Collins claimed she was the clear victor after they clashed last night in the first leaders' debate.

Brigette Morten, an advisor to the last National government, says Collins has limited campaign experience as a leader.

But she told Kate Hawkesby that Jacinda Ardern failed to show how she's used her political capital in the last three years to effect any real political change.

The debate that came hot on the heels of a 1News/Colmar Brunton poll last night that showed Labour on 48 per cent — enough to govern alone.

National was at 31 per cent, which was a one percentage point drop on the previous poll.

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