COMMENT:

There's nothing like opinion polls to get the chattering classes' gums beating.

The wide variation between the Newshub-Reid Research poll and 1 NEWS' Colmar Brunton last month had them frothing at the mouth. National loved the latter, while Labour loved the former - and the chatterers probably had the same feeling that Jim Bolger did after the 1993 election when he exclaimed "Bugger the pollsters".

It's the behind-the-scenes polls the parties have done for them that make the most interesting reading though, with their focus groups and the like.

As National heads back into its caucus today after a three-week break there'll be a lot of reflection as news of the Labour-commissioned UMR Research poll does the rounds.

Word around the traps has it that Labour's slipped slightly to 42 per cent while the Greens, who've been asserting themselves with cleaner cars, road safety and the ever so slight tilt at the up-until-now mortal sin of genetic modification gets a flicker, have picked up slightly to 9 per cent. New Zealand First has also increased slightly with its constant, and largely correct, claims that no one could do anything without them in Government.

So it's National that's bleeding and it looks set to haemorrhage, with growing whispers within the party that it'll be Simon Bridges' blood being spilled before too long. The party has dropped beneath the psychological barrier of 40 per cent, now sitting on 38.

It's the focus groups that'll concern National, with Bridges having about as much traction as a bald tyre. The last UMR poll apparently showed his unfavourable rating at more than 60 per cent, while those who favoured him were in the 20s.

The conclusion is that he can't win against Jacinda Ardern - but then regardless of who holds the job there's unlikely to be a change next year if history is anything to go by.

As much as Bridges bangs on about how lucky he is to have a caucus of talent there's only one who seems to be solidifying her position, as she smiles sweetly insisting she's just happy being the member for Papakura, which of course no one believes. The best thing Judith Collins did for her career was to stand down as a minister in the lead-up to the 2014 election.

That gave her the time to befriend the backbench. Like they say, idle hands are the devil's workshop.