First Queensland, now New South Wales: the National Party is coming around to the view that its survival depends on picking candidates who are seen to be more than just loyal followers of the Liberal Party line.

In a victory for product differentiation, the NSW Nats yesterday dumped long-serving senator Sandy Macdonald in favour of small businessman John Williams, described as “a colourful character unafraid to speak his mind” and “cut from the same cloth as Senator [Barnaby] Joyce”.

In the already-depleted Nationals Senate caucus, the Joyce view of the world looks to be on the rise. The other NSW National senator, Fiona Nash, has already shown rebel tendencies, and their Senate leader, Queensland’s Ron Boswell, is facing a choice between retirement and challenge by a Joyce ally. Macdonald had been the obvious successor as leader in the event of Boswell’s departure, so it’s back to the drawing board on that one.

Product differentiation has been tried before, of course, in the Joh for Canberra days of the 1980s, and many in the Queensland National Party clearly still hanker for his brand of authoritarian right-wing populism. But more sensible Nats know that if they go too far down that road, the Liberal Party will cut them loose, for the sake of its own survival: that’s the lesson the Liberals learned from the One Nation Queensland election of 1998.

NSW is a different case: it has always been the most harmonious state for relations between the Coalition parties. Harmony is a good thing, and no doubt the world could use more of it, but the lack of serious contest between Liberals and Nationals for so long makes it impossible to tell just what their respective bases of support are like.

In the lower house, the occasional three-cornered contests never seem to produce any National gains, and on their opposite flank the Nationals continue to lose seats to the ALP and independents.

The big thing to be said in Barnaby Joyce’s favour is that he won a Senate seat on his own (although only by the skin of his teeth): he didn’t depend on a joint ticket with the Libs. But Macdonald and Nash hold their seats courtesy of the Liberals. If he really wants to show some independence, Williams could offer to try his luck on a separate ticket.