The Sunday Star-Times quotes Katherine Rich as saying that accepting the help of the Exclusive Brethren cost National the last election. The full quote is in this longer piece about the Brethren and politics:
"I appreciate the Brethren thought they were being helpful to New Zealand in getting rid of Labour, but it's my personal opinion they lost us the election. The whiff of association was off-putting to a number of voters.
"My gut feeling is that their all-male line-up, in that famous Brethren press conference, made many women voters wonder just what their conservative vision for New Zealand was, and tipped the scales in favour of Labour," she said.
There's a lesson in here for National: don't crawl into bed with fundamentalist Christians who run anonymous smear campaigns. They are political poison, and the association will be punished at the ballot box.