While there’s a lot of similarities in how Australians vote between the House and the Senate, they’ve never voted exactly the same. For a start, there are more options on the Senate ballot paper than the House ballot paper. Small parties will not run in all House seats (sometimes they run in very few) and thus can only attract Senate votes in many seats. This means the bigger parties have traditionally done better in the House, where they have less competition.
In contrast, there are sometimes independent candidates who run locally, and don’t have an equivalent option on the Senate ballot. This has become much more of a factor in recent elections.
There is also the question of who can win, and their impact on the result. The major parties until recently were considered the only viable winners in the lower house, and the nature of the House meant the focus was on who would form government. Meanwhile the Senate has been a more viable opportunity for smaller parties to win seats, and a clear history of those electing having influence.
For this post I am going to look at how the difference between House voting and Senate voting has changed over the last half-century, and how it varies between seats across Australia.
Let’s start with the historical lens:
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Lines that dip low indicate that the party polled a higher vote for the House than the Senate. The chart dates back to 1974, as there have been no separate House and Senate elections over that period. There were numerous House-only and Senate-only elections in the 1950s, 1960s and early 1970s.
Labor and the combined Coalition parties have consistently had a higher House vote than Senate vote. 2025 was the first time that trend was interrupted, with Labor polling more votes in the Senate than the House, just slightly.
The Greens also polled more in the House than the Senate for just the third time in the party’s history. Traditionally the Greens (like the Democrats before them) did better in the upper house, but as the party has been more competitive in the House and had more competition from smaller left-leaning parties in the Senate, that advantage has been reversed.
The vote for all other parties is also intriguing. It has always been higher in the Senate, but the gap has varied quite a bit. It shrunk tremendously from 1987 to 1990, not because the Senate others vote went down, but because the House mostly caught up, with a vote of over 15% in the House for minor parties and independents excluding the Greens. The Senate vote kept growing, but the House vote fell back for some time.
The gap for other parties and independents widened to a new peak in 2013-2016, with the last GVT election and a double dissolution election making a wide range of parties viable in the Senate.
But more recently the others vote in the House has caught up on the Senate, primarily thanks to a surge in independents running in the House. It’s possible One Nation’s efforts in running candidates almost everywhere has helped.
Unsurprisingly, these national trends have not played out everywhere equally. This table breaks down the gap for the main groups by state:
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The ACT stands out tremendously, thanks to the impact of David Pocock. Pocock’s presence in the Senate significantly depresses the Labor and Greens votes compared to the House. We’ll see later on that the same phenomenon can be seen in many House seats in reverse, but those only make up small parts of large states, whereas the Pocock phenomenon covers the whole territory (although it is dampened in Bean by Jessie Price’s candidacy, with Price’s vote correlating strongly with Pocock’s vote at the booth level).
Labor’s overperformance in the Senate is focused in NSW, Victoria and Western Australia – three states with incumbent independent MPs. Interestingly Andrew Wilkie’s candidacy leads the Greens to have a big Senate bias, but not Labor. When I look at the individual seats, you can see that Labor did poll about 15% better in Clark in the Senate, but that is cancelled out by the other Tasmanian seats having quite strong House biases. I believe this is due to Jacqui Lambie’s presence across Tasmania cancelling out Wilkie’s big impact in Clark.
The Coalition’s Senate vote was generally lower everywhere. The ACT stands out (presumably reflecting that some Liberal voters have switched to Pocock), but also Queensland. After investigating the case of Queensland, I believe this reflects the vote for Gerard Rennick. His party polled 1.9% in the House and 4.7% in the Senate. If you subtract that gap from the LNP’s 4% Senate deficit, it brings the state roughly back in line with other states.
For each of these four blocs, I’ve also made a scatterplot showing each individual seat, and how the House and Senate vote compares.
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A majority of seats have a close relationship between the Labor vote in the two houses. The seats which stand out are quite obvious.
There’s a big cluster of seats where Labor’s House vote is repressed to around 10-20%, often with Senate votes above 30%. Quite a lot of these seats are in NSW, which has been marked in orange.
There are 14 seats where Labor polled 10% or more worse in the House than the Senate. An independent won eleven of those 14 seats. The only exceptions were Goldstein, Wannon and Cowper, where independents had serious contests against the independent. This dynamic has always existed, but usually on a much smaller scale.
On the other hand, the ACT seats of Canberra and Fenner stand out with a much higher Labor vote in the House than the Senate, due to David Pocock’s candidacy. The effect is muted in Bean due to Jessie Price.
There’s much less deviation in the Coalition vote, although those independent seats do have a Senate vote that implies a higher House vote than actually results. Standouts include Calare, Fowler, Calwell, Mayo, Indi, Wentworth, Mackellar and Curtin. I think the rest of the chart implies that the “natural” Liberal House vote in these seats would be about 5% higher.
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As for the Greens, there is again a close relationship which seems to naturally produce a slightly higher House vote than Senate vote. But that trend is up-ended in seats with prominent independents who cut into the Greens primary vote: Clark and Franklin in Tasmania stand out with a particularly high Greens Senate vote, but also teal seats like Curtin.
As for the “others” vote, the majority of seats follow a fairly tight pattern where the Senate vote is usually slightly higher than the House vote. But seats with prominent independents (win or lose) deviate from this pattern. And again, the ACT seats have the opposite pattern. Bean actually looks like it fits the standard pattern, just at the extreme end, with a teal independent falling just short in the House and a strong independent senator.
Kennedy also stands out with a huge vote for parties outside of the major parties. There was a 20% primary vote for Gerard Rennick and another 10% for One Nation.
Finally, I’ve included the same data in a map for Labor, the Coalition, the Greens and One Nation.