2015 North Sydney by-election

2015 North Sydney by-election

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The North Sydney seat in the House of Representatives
Registered	104,352
Turnout	78.37% 13.88
First party Second party Third party   IND Candidate Trent Zimmerman Stephen Ruff Arthur Chesterfield-Evans Party Liberal Independent Greens Popular vote 36,690 14,303 11,959 Percentage 48.20% 18.79% 15.71% Swing 12.84 18.79 0.36 TPP 60.23% 39.77% TPP swing 5.66 39.77
The Division of North Sydney covers 53 km² of Sydney's lower north shore.
MP before election Joe Hockey Liberal Elected MP Trent Zimmerman Liberal

A by-election for the Australian House of Representatives seat of North Sydney was held on 5 December 2015 from 8 am to 6 pm AEDT.^[1]

The trigger for the by-election was the 23 October parliamentary resignation of Joe Hockey, the backbench Liberal Member for North Sydney and former Abbott Coalition government Treasurer.^[2]

House of Representatives Speaker Tony Smith issued the writ for the by-election on 26 October. The electoral roll containing 104,352 electors closed on 2 November. Candidate nominations closed on 12 November, and the draw of the ballot paper order occurred on 13 November.^[3]

The by-election was won by Liberal candidate Trent Zimmerman, a former Hockey staffer, whose pre-selection had been controversial. Zimmerman won with 48.2 percent of the primary vote after a larger-than-predicted 12.8 percent swing against the Turnbull Coalition government. This was only the second time in North Sydney's history that the successful Liberal candidate did not obtain over 50 percent of the primary (first preference) vote and had to rely on preferences, the other time was in the 1961 general election. Zimmerman faced a double-digit primary vote swing − more than triple that of the 2015 Canning by-election − despite the absence of a Labor candidate. Labor have never been successful in the safe Liberal seat.^[1]

The Liberal two-candidate vote of 60.2 percent against independent Stephen Ruff compares to the previous election vote of 65.9 percent against Labor.^[1] The reduction of 5.7 percent cannot be considered a "two-party/candidate preferred swing" − when a major party is absent, preference flows to both major parties does not take place, resulting in asymmetric preference flows.^{[4][better source needed][5][better source needed]}

Ian Macfarlane attempted to defect from the Liberal party room to the National party room with accompanying demands for additional Nationals cabinet representation, and the Mal Brough / James Ashby diary controversy deepened in the last week of the campaign.^[6][7] Along with the unexpected by-election swing and Turnbull's significantly lessened personal ratings in the concurrent December Newspoll led journalists at several news outlets to opine Malcolm Turnbull's honeymoon to be over.^[8][9][10]

Zimmerman became the first openly-LGBTI member of the House of Representatives.^[11][12]