Electoral Pendulum
The 2004 election saw a House of 150 seats with 87 Coalition members, 60 Labor members, and three independents. Immediately following the 2004 election, to win government outright — ie. to have 76 seats in a house of 150 — Labor needed to win 16 additional seats. The mathematics is simple: 60 + 16 = 76. If Labor only wins 15 seats, it would still form a minority government, but it would need the support of one of the two independents.
There has been one by-election since 2004, in the seat of Werriwa. That by-election saw Chris Hayes (Labor) replace Mark Latham (Labor). It did not affect the number of seats Labor needs to win.
The have also been redistributions in New South Wales, Queensland and the Australian Capital Territory since the 2004 election. The redistributions saw no change to the number of seats in the House (150). One Coalition seat in New South Wales (Gwydir) was abolished and a notionally Coalition seat (Flynn) was created in Queensland. This does not affect the number of seats Labor needs to win.
The redistributions also saw two seats notionally change sides. Parramatta, currently held by Labor, became a notionally Liberal seat. And, Macquarie, currently held by the Liberals, became a notionally Labor seat. Because these notional moves cancel each other out, they do not affect the number of seats Labor needs to win.
In the seat of Calare, independent member Peter Andren has announced he will not stand for election in Calare in 2007. This changes Calare from an independent seat to a notionally Coalition seat. As a consequence, it does not change the number of seats Labor currently holds, nor the number of seats Labor needs to win government. However, it increases by one the number of seats the Coalition can lose before it loses government in its own right from 12 to 13.
As a result of the above, the Coalition notionally holds 88 seats. Labor notionally holds 60 seats. and the independents hold 2. Nothing has changed for Labor. Sixteen seats would give it outright government. Fifteen seats would give Labor minority government.
The Pendulum
The following table is a linear presentation of the electoral pendulum. The seats are ranked from the safest Labor seat to the safest Coalition seat. The TPP vote shares have been adjusted to take account of redistributions in ACT, NSW and Qld using this report from the Australian Electoral Commission. The notional state of the current Parliament is underlined with a thick line: 88 seats for the Coalition and 60 seats for Labor. If Labor wins the next 15 seats it would have 75 and the Coalition 73.
With the hypothetical uniform swing, using the election calculator, if Labor won 51.4 per cent of the tw- party preferred (TPP) vote share it would win 75 seats. The last seat to fall under that swing would be Bennelong.
| Division | State | Adjusted 2004 ALP TPP in seat (%) | Uniform swing to Labor | Labor seats | Coalition seats | Labor seats gained |
| If Labor wins no seats in 2007, the result would be –> | 0 | 148 | −60 | |||
| Batman | Vic | 71.32 | −21.32 | 1 | 147 | −59 |
| Grayndler | NSW | 71.19 | −21.19 | 2 | 146 | −58 |
| Melbourne | Vic | 71.14 | −21.14 | 3 | 145 | −57 |
| Sydney | NSW | 67.38 | −17.38 | 4 | 144 | −56 |
| Wills | Vic | 66.90 | −16.90 | 5 | 143 | −55 |
| Blaxland | NSW | 65.23 | −15.23 | 6 | 142 | −54 |
| Gellibrand | Vic | 64.95 | −14.95 | 7 | 141 | −53 |
| Gorton | Vic | 64.90 | −14.90 | 8 | 140 | −52 |
| Scullin | Vic | 64.79 | −14.79 | 9 | 139 | −51 |
| Watson | NSW | 64.56 | −14.56 | 10 | 138 | −50 |
| Throsby | NSW | 63.82 | −13.82 | 11 | 137 | −49 |
| Fowler | NSW | 63.32 | −13.32 | 12 | 136 | −48 |
| Fraser | ACT | 63.32 | −13.32 | 13 | 135 | −47 |
| Denison | Tas | 63.29 | −13.29 | 14 | 134 | −46 |
| Port Adelaide | SA | 62.91 | −12.91 | 15 | 133 | −45 |
| Reid | NSW | 62.08 | −12.08 | 16 | 132 | −44 |
| Chifley | NSW | 61.97 | −11.97 | 17 | 131 | −43 |
| Cunningham | NSW | 61.62 | −11.62 | 18 | 130 | −42 |
| Hunter | NSW | 61.09 | −11.09 | 19 | 129 | −41 |
| Canberra | ACT | 59.91 | −9.91 | 20 | 128 | −40 |
| Maribyrnong | Vic | 59.47 | −9.47 | 21 | 127 | −39 |
| Shortland | NSW | 59.24 | −9.24 | 22 | 126 | −38 |
| Newcastle | NSW | 59.09 | −9.09 | 23 | 125 | −37 |
| Lalor | Vic | 58.79 | −8.79 | 24 | 124 | −36 |
| Kingsford Smith | NSW | 58.73 | −8.73 | 25 | 123 | −35 |
| Griffith | Qld | 58.48 | −8.48 | 26 | 122 | −34 |
| Charlton | NSW | 58.40 | −8.40 | 27 | 121 | −33 |
| Calwell | Vic | 58.19 | −8.19 | 28 | 120 | −32 |
| Fremantle | WA | 57.76 | −7.76 | 29 | 119 | −31 |
| Lingiari | NT | 57.66 | −7.66 | 30 | 118 | −30 |
| Franklin | Tas | 57.59 | −7.59 | 31 | 117 | −29 |
| Barton | NSW | 57.57 | −7.57 | 32 | 116 | −28 |
| Hotham | Vic | 57.40 | −7.40 | 33 | 115 | −27 |
| Oxley | Qld | 57.12 | −7.12 | 34 | 114 | −26 |
| Werriwa | NSW | 56.94 | −6.94 | 35 | 113 | −25 |
| Perth | WA | 56.73 | −6.73 | 36 | 112 | −24 |
| Prospect | NSW | 56.40 | −6.40 | 37 | 111 | −23 |
| Corio | Vic | 55.64 | −5.64 | 38 | 110 | −22 |
| Lilley | Qld | 55.40 | −5.40 | 39 | 109 | −21 |
| Brand | WA | 54.65 | −4.65 | 40 | 108 | −20 |
| Jagajaga | Vic | 54.40 | −4.40 | 41 | 107 | −19 |
| Capricornia | Qld | 54.01 | −4.01 | 42 | 106 | −18 |
| Brisbane | Qld | 53.94 | −3.94 | 43 | 105 | −17 |
| Melbourne Ports | Vic | 53.74 | −3.74 | 44 | 104 | −16 |
| Lyons | Tas | 53.68 | −3.68 | 45 | 103 | −15 |
| Bruce | Vic | 53.48 | −3.48 | 46 | 102 | −14 |
| Banks | NSW | 53.22 | −3.22 | 47 | 101 | −13 |
| Lowe | NSW | 53.03 | −3.03 | 48 | 100 | −12 |
| Rankin | Qld | 52.98 | −2.98 | 49 | 99 | −11 |
| Chisholm | Vic | 52.65 | −2.65 | 50 | 98 | −10 |
| Ballarat | Vic | 52.23 | −2.23 | 51 | 97 | −9 |
| Holt | Vic | 51.51 | −1.51 | 52 | 96 | −8 |
| Isaacs | Vic | 51.48 | −1.48 | 53 | 95 | −7 |
| Richmond | NSW | 51.44 | −1.44 | 54 | 94 | −6 |
| Adelaide | SA | 51.33 | −1.33 | 55 | 93 | −5 |
| Bendigo | Vic | 50.96 | −0.96 | 56 | 92 | −4 |
| Cowan | WA | 50.78 | −0.78 | 57 | 91 | −3 |
| Macquarie # | NSW | 50.47 | −0.47 | 58 | 90 | −2 |
| Swan | WA | 50.08 | −0.08 | 59 | 89 | −1 |
| Hindmarsh | SA | 50.06 | 0.00 | 60 | 88 | 0 |
| Kingston | SA | 49.93 | 0.07 | 61 | 87 | 1 |
| Bonner | Qld | 49.49 | 0.51 | 62 | 86 | 2 |
| Wakefield | SA | 49.33 | 0.67 | 63 | 85 | 3 |
| Parramatta # | NSW | 49.17 | 0.83 | 64 | 84 | 4 |
| Makin | SA | 49.07 | 0.93 | 65 | 83 | 5 |
| Braddon | Tas | 48.87 | 1.13 | 66 | 82 | 6 |
| Hasluck | WA | 48.18 | 1.82 | 67 | 81 | 7 |
| Stirling | WA | 47.96 | 2.04 | 68 | 80 | 8 |
| Wentworth | NSW | 47.49 | 2.51 | 69 | 79 | 9 |
| Bass | Tas | 47.37 | 2.63 | 70 | 78 | 10 |
| Solomon | NT | 47.19 | 2.81 | 71 | 77 | 11 |
| Moreton | Qld | 47.17 | 2.83 | 72 | 76 | 12 |
| Lindsay | NSW | 47.08 | 2.92 | 73 | 75 | 13 |
| Eden-Monaro | NSW | 46.73 | 3.27 | 74 | 74 | 14 |
| Bennelong | NSW | 45.87 | 4.13 | 75 | 73 | 15 |
| Dobell | NSW | 45.16 | 4.84 | 76 | 72 | 16 |
| Deakin | Vic | 45.03 | 4.97 | 77 | 71 | 17 |
| McMillan | Vic | 45.01 | 4.99 | 78 | 70 | 18 |
| Corangamite | Vic | 44.68 | 5.32 | 79 | 69 | 19 |
| Boothby | SA | 44.63 | 5.37 | 80 | 68 | 20 |
| Page | NSW | 44.54 | 5.46 | 81 | 67 | 21 |
| Blair | Qld | 44.31 | 5.69 | 82 | 66 | 22 |
| La Trobe | Vic | 44.17 | 5.83 | 83 | 65 | 23 |
| Herbert | Qld | 43.76 | 6.24 | 84 | 64 | 24 |
| Kalgoorlie | WA | 43.70 | 6.30 | 85 | 63 | 25 |
| Paterson | NSW | 43.68 | 6.32 | 86 | 62 | 26 |
| McEwen | Vic | 43.58 | 6.42 | 87 | 61 | 27 |
| Cowper | NSW | 43.25 | 6.75 | 88 | 60 | 28 |
| Longman | Qld | 43.25 | 6.75 | 89 | 59 | 29 |
| Sturt | SA | 43.20 | 6.80 | 90 | 58 | 30 |
| Robertson | NSW | 43.13 | 6.87 | 91 | 57 | 31 |
| Petrie | Qld | 42.55 | 7.45 | 92 | 56 | 32 |
| Gippsland | Vic | 42.30 | 7.70 | 93 | 55 | 33 |
| Flynn | Qld | 42.28 | 7.72 | 94 | 54 | 34 |
| Hinkler | Qld | 41.66 | 8.34 | 95 | 53 | 35 |
| Hughes | NSW | 41.45 | 8.55 | 96 | 52 | 36 |
| Higgins | Vic | 41.24 | 8.76 | 97 | 51 | 37 |
| Kennedy* | Qld | 41.14 | 8.86 | 98 | 51 | 38 |
| Dickson | Qld | 41.11 | 8.89 | 99 | 50 | 39 |
| Bowman | Qld | 41.10 | 8.90 | 100 | 49 | 40 |
| Dunkley | Vic | 40.62 | 9.38 | 101 | 48 | 41 |
| Gilmore | NSW | 40.59 | 9.41 | 102 | 47 | 42 |
| Canning | WA | 40.46 | 9.54 | 103 | 46 | 43 |
| Kooyong | Vic | 40.42 | 9.58 | 104 | 45 | 44 |
| Dawson | Qld | 40.01 | 9.99 | 105 | 44 | 45 |
| Goldstein | Vic | 39.97 | 10.03 | 106 | 43 | 46 |
| North Sydney | NSW | 39.96 | 10.04 | 107 | 42 | 47 |
| Leichhardt | Qld | 39.74 | 10.26 | 108 | 41 | 48 |
| Ryan | Qld | 39.58 | 10.42 | 109 | 40 | 49 |
| Forrest | WA | 39.55 | 10.45 | 110 | 39 | 50 |
| Menzies | Vic | 39.33 | 10.67 | 111 | 38 | 51 |
| Moore | WA | 39.17 | 10.83 | 112 | 37 | 52 |
| Fisher | Qld | 39.02 | 10.98 | 113 | 36 | 53 |
| Flinders | Vic | 38.89 | 11.11 | 114 | 35 | 54 |
| Macarthur | NSW | 38.85 | 11.15 | 115 | 34 | 55 |
| Warringah | NSW | 38.71 | 11.29 | 116 | 33 | 56 |
| Casey | Vic | 38.65 | 11.35 | 117 | 32 | 57 |
| Greenway | NSW | 38.65 | 11.35 | 118 | 31 | 58 |
| Calare* | NSW | 38.59 | 11.41 | 119 | 30 | 59 |
| Forde | Qld | 38.48 | 11.52 | 120 | 29 | 60 |
| Tangney | WA | 38.25 | 11.75 | 121 | 28 | 61 |
| Wide Bay | Qld | 37.79 | 12.21 | 122 | 27 | 62 |
| Wannon | Vic | 37.63 | 12.37 | 123 | 26 | 63 |
| Fairfax | Qld | 37.59 | 12.41 | 124 | 25 | 64 |
| Hume | NSW | 37.16 | 12.84 | 125 | 24 | 65 |
| Pearce | WA | 37.06 | 12.94 | 126 | 23 | 66 |
| Aston | Vic | 36.85 | 13.15 | 127 | 22 | 67 |
| Cook | NSW | 36.72 | 13.28 | 128 | 21 | 68 |
| Lyne | NSW | 36.59 | 13.41 | 129 | 20 | 69 |
| Mayo* | SA | 36.41 | 13.59 | 130 | 19 | 70 |
| New England* | NSW | 36.41 | 13.59 | 131 | 19 | 71 |
| Berowra | NSW | 36.18 | 13.82 | 132 | 18 | 72 |
| Grey | SA | 36.18 | 13.82 | 133 | 17 | 73 |
| McPherson | Qld | 36.06 | 13.94 | 134 | 16 | 74 |
| Curtin | WA | 35.38 | 14.62 | 135 | 15 | 75 |
| Mackellar | NSW | 34.54 | 15.46 | 136 | 14 | 76 |
| Fadden | Qld | 34.10 | 15.90 | 137 | 13 | 77 |
| Indi | Vic | 33.71 | 16.29 | 138 | 12 | 78 |
| Farrer | NSW | 33.37 | 16.63 | 139 | 11 | 79 |
| Bradfield | NSW | 32.45 | 17.55 | 140 | 10 | 80 |
| Parkes | NSW | 32.44 | 17.56 | 141 | 9 | 81 |
| Groom | Qld | 31.19 | 18.81 | 142 | 8 | 82 |
| Moncrieff | Qld | 30.47 | 19.53 | 143 | 7 | 83 |
| Barker | SA | 30.12 | 19.88 | 144 | 6 | 84 |
| O’Connor | WA | 29.61 | 20.39 | 145 | 5 | 85 |
| Mitchell | NSW | 29.32 | 20.68 | 146 | 4 | 86 |
| Riverina | NSW | 29.15 | 20.85 | 147 | 3 | 87 |
| Maranoa | Qld | 28.95 | 21.05 | 148 | 2 | 88 |
| Murray | Vic | 25.92 | 24.08 | 149 | 1 | 89 |
| Mallee | Vic | 25.25 | 24.75 | 150 | 0 | 90 |

Want to find out more?
- The Australian Electoral Commission
- Simon Jackman’s electoral Pendulum
- Peter Brent’s Mumble election site
- William Bowe’s The Poll Bludger