Oceania: Polling and Politics

Australia uses Alternative Vote (also called Instant Runoff Voting) for its House of Representatives and Single Transferable Vote for the Senate. The combination is effectively the most preferential-vote-friendly system in the world. Voters rank candidates in order; lowest-ranked candidates are eliminated and their preferences redistributed until majorities emerge. This produces winners with broad consent but makes polling more complex than in simple plurality systems. The headline figure to watch in Australian polling is usually the two-party-preferred number — the projected share between the two leading parties after preferences distribute — rather than primary vote share.

New Zealand made the more dramatic reform: in 1996 it switched from First Past the Post to Mixed-Member Proportional. Each voter now casts two ballots, one for a constituency MP and one for a party. Proportional list seats are added to make the overall composition of parliament roughly proportional to the party-vote totals. The five-percent threshold is a key inflection point: parties hovering just below or above it can swing the entire coalition arithmetic.

The Australian polling industry experienced a high-profile collective miss in the 2019 federal election, when essentially every major firm understated the eventual winner's vote share. The post-mortem produced widespread methodological reform, including more aggressive past-vote weighting, more diverse mode mixes, and renewed industry transparency standards. The lessons were taken seriously, and the next cycle's polling was visibly more cautious.

Both countries have small enough electorates that a polling sample of one or two thousand can produce relatively narrow margins of error, but their geographic spread, indigenous and immigrant communities, and rural-urban polarisation all complicate sampling. As elsewhere, the careful reader should focus on averages and trends rather than individual polls.