The South Australian state election will be held on March 21. Preferential voting will be used to elect members for all 47 single-member lower house seats. This is the same system as used for federal House of Representatives elections.

Some Australian conservatives are advocating Australia return to first past the post (FPTP), but a conservative government introduced preferential voting in 1918 to stop vote splitting between two conservative parties. Right-wing preferences helped the Coalition maintain its grip on power from 1949 to 1972. Preferential voting is far superior to FPTP.

After Labor’s landslide at the May 2025 federal election, some right-wingers have complained that preferential voting gave Labor too many seats. They want Australia to revert to FPTP, where there are no preferences. In FPTP, the candidate with the most votes wins the seat.

National primary votes at the election were 34.6% Labor, 31.8% Coalition, 12.2% Greens, 6.4% One Nation and 15.0% for all Others. After preferences, Labor defeated the Coalition by 55.2–44.8 and won 94 of the 150 House of Representatives seats (63% of seats). In both two-party and seat share, this was Labor’s biggest win since 1943.

While Labor’s margin expanded after preferences, they won the national primary vote by 2.8%. Analyst Kevin Bonham said that on primary votes, Labor would have won 86 seats to 57 for the Coalition (actual 94 to 43). Labor’s primary votes were much more efficiently distributed than the Coalition’s.

Labor won a disproportionate seat share at the election, but this occurs with single-member systems, particularly with a blowout result. Those complaining about Labor’s big majority should advocate switching to proportional representation, not FPTP.

The United Kingdom 2024 election was held using FPTP. Labour won 411 of the 650 seats........

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