Tauranga MP and leader of the opposition Simon Bridges has taken a hit in the latest political opinon poll.

Simon's preferred Prime Minister rating was down three points to just seven per cent, while Prime Minister Jacinda Ardern was up two points to her highest-ever rating of 42 per cent.

The One News/Colmar Brunton poll was the first since the Jami-Lee Ross furore broke.

It also shows National MP and former leadership aspirant Judith Collins is breathing down Bridges' neck – she's at five per cent in the preferred Prime Minister rankings, while NZ First's Winston Peters was on four per cent.

The poll predictably shows National has dropped below Labour in the wake of the Jami-Lee Ross affair.

National dropped two points to 43 per cent, while Labour was gifted three points to have 45 per cent of the poll. The Greens were to seven per cent, while NZ First remained steady on five per cent and ACT dropped off the bottom of the register.

The poll shows that on these numbers, Labour would have 54 seats and could govern with just the Green Party and its eight seats, taking it beyond the 61-seat threshold.

National would have 53 seats, and would be way off governing.

It's the first poll since Jami-Lee Ross resigned from National, alleging electoral fraud and releasing the damaging, secretly-recorded conversation with Bridges. It is also the first poll since the leaking of Bridges' expenses.