https://doi.org/10.1177/0263395718815786 Politics 1–16 © The Author(s) 2018 Article reuse guidelines: sagepub.com/journals-permissions DOI: 10.1177/0263395718815786 journals.sagepub.com/home/pol Explaining the Australian marriage equality vote: An aggregate-level analysis Timothy B Gravelle The University of Melbourne, Australia Andrea Carson La Trobe University, Australia Abstract The Australian public voted in November 2017 in favour of changing the law to allow for same- sex marriage – only the second such national popular vote after Ireland in 2015. Though 61.6% of the Australian public voting in the Marriage Law Postal Survey voted Yes in support of marriage equality, this support was not uniformly distributed across the country, with support at the electoral division level varying between 26.1% and 83.7%. What, then, explains such variation in support for same-sex marriage among the Australian public? In this article, we advance an aggregate, electoral division-level explanation of the Yes vote that links support for the legalisation of same-sex marriage to a set of local-level political and socio-demographic factors. Keywords Australia, same-sex marriage, voting behaviour Received: 14th May 2018; Revised version received: 20th September 2018; Accepted: 16th October 2018 Introduction On 15 November 2017, the Australian Bureau of Statistics (ABS) announced the results of the Marriage Law Postal Survey, ending a contentious, months-long campaign and confirming majority support (61.6%) for legalising same-sex marriage among the Australian public. With just over three in five Australians responding Yes to the survey, the right-of-centre Liberal-National Coalition government of then-Prime Minister Malcolm Turnbull committed to legislating marriage equality by the end of the year, ful- filling this promise on 7 December 2017. This means Australia has joined the 25 countries Corresponding author: Timothy B Gravelle, School of Social and Political Sciences, The University of Melbourne, John Medley Building, Parkville, VIC 3010, Australia. Email: tim.gravelle@unimelb.edu.au 815786POL 0 0 10.1177/0263395718815786PoliticsGravelle and Carson research-article 2018 Article