New leaders almost always get a boost in the polls, and with Labour at 23% to 24% in most polls it is inevitable Labour will get a boost with the election of Jacinda Ardern as leader.
I’ve gone back through all the One News polls since 1974 to look at what has been the poll boost has been for a new leader (excepting those after an election loss). Here’s the boosts:
- Geoffrey Palmer 1989, 16%
- Helen Clark, 1993, 7%
- Jim McLay 1984, 7%
- David Lange 1983, 6%
- Mike Moore, 1990, 5%
- Jenny Shipley, 1997, 4%
- Jim Bolger 1986, 4%
- Don Brash 2003, 4%
- Bill English 2001, -1%
- John Key 2006, -3%
So Palmer gave Labour a huge boost when he was elected to replace Lange. It did not last though and half of it was gone two months later and of course he was rolled a year later.
Clark and McLay both got 7% boosts for their parties from their elections, and neither actually ended up winning the next election. Of course they were not elected eight weeks before an election.
Mike Moore was and his party boost was 5%.
The interesting that is that John Key did not initially give National a poll boost. People forget that National under Brash was very popular in 2006. It was at 49% in the polls in Oct 2006 under Brash and after Key took over was at 46% the following February. So you can not get a boost and go on to be very popular.
Don Brash got an initial 4% boost for National by becoming leader, but the big boost was two months later after his Orewa speech where National went up a further 17%.
So what will Ardern’s boost for Labour be? Will it be the same as Bolger, Shipley and Moore at 4% to 5% or will it be larger, or smaller?