| Country: | Victoria |
| Type: | parliamentary |
| Ongoing: | no |
| Previous Election: | 2014 Victorian state election |
| Previous Year: | 2014 |
| Next Election: | 2018 Victorian state election |
| Next Year: | 2018 |
| Election Date: | 31 October 2015 |
| Seats For Election: | Electoral district of Polwarth in the Victorian Legislative Assembly |
| Candidate1: | Richard Riordan |
| Party1: | Liberal Party of Australia |
| Popular Vote1: | 17,798 |
| Percentage1: | 49.6% |
| Swing1: | 5.7pp |
| Candidate2: | Joe Miles |
| Party2: | Australian Greens |
| Popular Vote2: | 5,715 |
| Percentage2: | 15.9% |
| Swing2: | 4.9pp |
| Candidate3: | David O'Brien |
| Party3: | National Party of Australia |
| Popular Vote3: | 4,292 |
| Percentage3: | 12.0% |
| Swing3: | 12.0pp |
| MP | |
| Before Election: | Terry Mulder |
| Before Party: | Liberal Party of Australia |
| After Election: | Richard Riordan |
| After Party: | Liberal Party of Australia |
A by-election for the seat of Polwarth in the Victorian Legislative Assembly was held on 31 October 2015. The by-election was triggered by the resignation of Terry Mulder on 3 September 2015. Former Premier of Victoria, Denis Napthine, resigned his seat representing the adjacent district of South-West Coast on the same day as Mulder.[1] The by-election for South-West Coast was held on the same day.
| 8 candidates in ballot paper order | |||||
|---|---|---|---|---|---|
| Party | Candidate | width=75% | Background | ||
| Greens | Joe Miles | Welfare officer & disability support,[2] anti-fracking organiser in Victoria's South West & Barwon region.[3] | |||
| Democratic Labour | Carmel Kavanagh | Leads a charity providing refugee advocacy, housing and resettlement assistance.[4] | |||
| Country | Melinda Cass | Farmer from Cressy.[5] | |||
| National | David O'Brien | Former member of the Victorian Legislative Council for Western Victoria Region.[6] | |||
| Independent | Brendan Eckel | A Ballarat-based psychiatric nurse. | |||
| Sex Party | Meredith Doig | Company director and management consultant. Member of the university council for Federation University Australia.[7] President of the Rationalist Society of Australia.[8] | |||
| Liberal | Richard Riordan | Colac businessman, owner of Riordan Colac Hire, board member of the Corangamite Catchment Management Authority, former chairman of Colac Area Health board.[9] | |||
| Christians | Geoff Rogers | Candidate for federal seat of Lalor at the 2013 federal election.[10] | |||
The Labor government did not contest the by-elections in the safe Liberal seats of Polwarth and South-West Coast.[11]
Candidate volunteers attempt to distribute how-to-vote cards to voters at polling booths which show the candidate's suggested preference allocation. Candidates and parties which suggested preferences are shown in each column of the table below. The Australian Sex Party ran an open card at this by-election.
| Greens[12] | DLP | Country[13] | National | Eckel | Sex | Liberal | Christians | |
|---|---|---|---|---|---|---|---|---|
| Greens | 1 | 8 | 8 | 8 | No card | 6 | 7 | |
| DLP | 7 | 1 | 3 | 4 | 5 | 2 | ||
| Country | 6 | 4 | 1 | 7 | 3 | 5 | ||
| National | 4 | 5 | 7 | 1 | 2 | 3 | ||
| Eckel | 5 | 3 | 2 | 6 | 7 | 6 | ||
| Sex | 2 | 7 | 4 | 5 | 1 | 8 | 8 | |
| Liberal | 3 | 6 | 6 | 2 | 1 | 4 | ||
| Christians | 8 | 2 | 5 | 3 | 4 | 1 | ||
|- style="background-color:#E9E9E9"! colspan="6" style="text-align:left;" |After distribution of preferences
The VEC distributed preliminary preferences until a candidate exceeded 50 per cent of the vote, in this case Liberal candidate Richard Riordan.[14]