a little loose conversation - what now for National?

It's an excruciatingly close result, but what does this mean for Don? he's nearly 65, he's not won the election, and there John Key (and no doubt others) must already be thinking about the numbers for a year's time.

Will we see National have five different leaders in five subsequent elections?

Of course there is much coalition chat to go, and Brash has made a huge difference to his party (to give him all the credit is probably not fair on others behind the scenes) but maybe His Work Here Is Done?