Last week, I posted data showing the Nick Xenophon Team vote at the 2016 Senate election broken down by state electorate.
In the process of completing my guide to the South Australian state election, I noticed the trend in terms of which seats popped up with very high NXT votes. It appeared that numerous safe Liberal seats ranked highly in terms of NXT vote, while the safer Labor seats ranked more lowly.
It’s undoubtedly true that Xenophon takes votes from all parties – when his vote has been particularly high, both major parties have suffered big hits. But the vote does tend to be higher in electorates normally considered ‘safe Liberal’.
We saw this clearly at the 2016 federal election – the NXT vote was highest in Mayo, Barker and Grey, all places where the Liberal Party would normally walk all over Labor in a head-to-head fight.
And when I compared the 2016 NXT Senate data to the Liberal two-party-preferred vote in each new state seat, there is a trend where the NXT vote is higher in stronger Liberal seats.
It’s not a perfect trend, but the correlation is around 0.558.
So what does this suggest about the impact that Nick Xenophon’s SA Best could have on the next election?
We obviously don’t know how highly the party will poll – they have only announced a handful of candidates, so it’s conceivable they won’t run a full ticket. But it seems more likely that a large vote for SA Best will hit hardest in Liberal seats, particularly in seats where the Liberal Party would normally not need to campaign hard. In contrast, the safer Labor seats are likely to stay safe, unless SA Best polls particularly strongly.