I see there's been a smattering of discussion at Public Address on (amongst other things) leadership succession in a post-Key National Party.
Here are the findings of Public Pollsters over the last 5 years.
HD = Herald-DigiPoll
FI = Fairfax Ipsos
CB = Colmar Brunton
(Note: Only One News Colmar Brunton provide Don't Know figures. With the other polls, I'm reluctant to simply subtract the aggregate potential leader figures from 100% to reach a Don't Know figure because I can't be sure there weren't other Nat politicians receiving smaller shares of support who were excluded from the tables in the respective poll reports)
Next National Party Leader Polls
Poll Politician
HD (Aug 2015) English 30 Joyce 14 Bennett 11 Bridges 7
FI (Sep 2014) English 33 Joyce 22 Bennett 11 Bridges 9
CB (Sep 2014) English 28 Joyce 16 Bennett 7 Collins 2
Woodhouse 2 Don't Know 41
CB (July 2013) English 23 Joyce 16 Collins 11 Other 5
Don't Know 45
HD (June 2013) English 30 Joyce 25 Collins 13
HD (Nov 2011) English 27 Joyce 19 Collins 16 Brownlee 11
Joyce's stocks appear to have taken a bit of a tumble (albeit in the context of a long-term roller-coaster ride), Bennett's nowhere near as popular as many pundits seem to assume, nor is Bridges. Collins and Brownlee were contenders back in 2011, but the Oravida (May 2014) and Dirty Politics (August 2014) scandals pretty much did for the reputation of the former while the latter's gone completely off the radar. That leaves Wild Bill English as the perpetual frontrunner. Interesting, given his unpopularity back in the early Zeros, leading National to its historic low of 21% at the 2002 General Election. The Finance Minister and Deputy PM appears to have rehabilitated his reputation as a future leader. Bear in mind, though, that less than a third of respondents choose English (there's always a significant Don't Know factor) and, if the Sep 2014 Colmar Brunton is anything to go by, less than a quarter of non-National Party supporters favour him. .
The Sep 2014 Colmar Brunton supplies not only Entire Sample figures (Total) but also the breakdown specifically for National Party supporters (National). They've also provided enough detail to allow me to calculate potential leader figures among the supporters of all parties other than National (Other Parties). This segment (making up roughly half of all respondents) is dominated by Opposition party supporters but also includes those voting for the Conservatives, the minor parties of Government and the Undecideds.
Colmar Brunton also supply stats for those demographics more likely than average to support (variously) English and Joyce.
Next National Party Leader Colmar Brunton (Sep 2014)
Politician Total National Other Parties
English 28 33 23
Joyce 16 23 9
Bennett 7 7 7
Collins 2 2 2
Woodhouse 2 1 3
Other 4 3 5
Don't Know 41 32 50
Above Average Support for English
Wellington residents 39
Men 34
Above Average Support for Joyce
Age 55 + 24
National Supporters 23
High Income 22
Addendum
Latest Poll from Labour's UMR:
Next National Party Leader Polls
Poll Politician
UMR (Oct 2016) English 21 Joyce 16 Bennett 11 Collins 6
