The Dim-Post argues the Prime Minister's support for gay marriage is a huge stroke of luck for Labour. In the next Labour-led government, there won't be any pressure from Labour's activists to enact gay marriage while Labour's own Louisa Wall gets the credit for bringing the change about.
But the more I think about it the more it seems the biggest winner from the gay marriage debate is the Prime Minister and his government. As I've argued here previously, the biggest impediment to a third-term for National in 2014 (on current polling) is a lack of allies to the right. The most viable new kid on the block is Colin Craig's Conservative Party (CCCP). Craig's own positioning on the debate - by making outrageous statements on homosexuality - is both opportunistic and playing to the ultra-conservative base. It's likely he'll pick up votes from disenchanted social conservatives who would otherwise vote National or Act (and maybe even NZ First).
It's not unreasonable to guess the CCCP might be propelled into parliament off the back of this debate, even though it appears to be largely over. With Act on its way out (bringing in no extra MPs the people of Epsom could very well just throw their lot in with Paul Goldsmith) and no other potential partners, the CCCP taking 5% of the party vote wouldn't be impossible. Craig certainly has the money to throw at the party.
All of this means the chances of there being a new ally for National post 2014 just got a lot better. Even if Labour are able to repeat their 1999 performance (38% of the party vote) off the back of opposition to the mixed ownership model, and the Greens are again above 10%, a National-led government with support from the Conservatives, United and the Maori Party could still hang on with the same level of support. The likelihood of this outcome is even greater if the threshold is decreased to 4% of party votes (abolishing the one-seat rule would also have no impact).
The net result, though, is that National will be able to stay in office 2014 - 2017, even with a reduced share of the party. By then gay marriage will have been enacted, the sky wouldn't have fallen in and Craig will probably have to find another issue to make stupid comments about.