FACTBOX-Australia's election: how it works

(Reuters) - Australia will hold national elections on November 24, with conservative Prime Minister John Howard hoping for a fifth term in office, and Labor's Kevin Rudd hoping his party can win back power after 11 years in opposition.

The following facts explain how the elections work in Australia.

* Australia has a bi-cameral parliament, based on Britain's Westminster system. The government is formed by the party with a majority in the lower House of Representatives chamber.

* All 150 seats in the House of Representatives will be up for election. The centre-left Labor party needs to win 16 more seats to form an outright majority and win power.

* Going into the election, Prime Minister John Howard's Liberal Party held 74 seats, and governs in coalition with the smaller rural-based National Party, which had 12 seats, and the Liberal-Country Party's one member.

* Voting is compulsory for about 13 million Australians, who must register when they turn 18. Those who don't vote face fines.

* Australia is divided into 150 electorates. Each seat has about 90,000 voters. Lawmakers are elected for a three-year term, although the government can call elections earlier.

* Electorates are based on population, leading to vast differences in size. The inner Sydney seat of Wentworth covers 26 sq km (10 sq mile), while the Western Australian seat of Kalgoorlie covers 2.2 million sq km (849,500 sq mile), an area the size of France, Spain, Germany, Italy, Poland and Britain combined.

* Australia has a preferential voting system for elections to the lower house, with voters marking their ballot papers "1,2,3..." in order of preference.