National will need to make history to capture Phil Goff's Mt Roskill seat in an upcoming byelection, the party's president Peter Goodfellow says.
Following his election as Auckland Mayor, Goff will resign from Parliament next week. That will allow for a byelection in Mt Roskill before Christmas.
Goodfellow said National would select a candidate on October 19, with nominations opening next week.
However, the selection of Mt Roskill-based list MP Dr Parmjeet Parmar is all but certain.
Goodfellow said it will be "very difficult" to capture Mt Roskill, as no government had ever won a byelection off the Opposition.