FACTBOX: Key facts on likely Slovenia coalition after poll

(Reuters) - Slovenia's opposition centre-left Social Democrats (SD) defeated the centre-right Slovenian Democratic Party of Prime Minister Janez Jansa in Sunday's parliamentary election, according to preliminary official results.

Slovenia's parliament has 90 seats, of which two belong to representatives of Italian and Hungarian minorities.

Following are key facts on the four parties that are likely to form a new government coalition.

SOCIAL DEMOCRATS (SD) - Likely to get 29 seats, the party has been the main opposition grouping during Jansa's rule and is led by European Parliament member Borut Pahor. Descendant of the former Communist Party, it pledges to liberalize the economy but also increase lowest salaries, provide more support for the elderly, jobless and sick, improve public health and cut defence sending. Has agreed coalition with fellow centre-left LDS and Zares.

ZARES - Nine seats. A centre-left party formed last year by seven parliament deputies who defected from the Liberal Democrats. Headed by Gregor Golobic, a close ally of late centre-left prime minister and former president Janez Drnovsek, it urges more market competition and further cuts in public spending.

LIBERAL DEMOCRATIC PARTY (LDS) - Five seats. Slovenia's strongest party for 12 years until it lost the 2004 election, after which it broke up. A newcomer to politics, lawyer Katarina Kresal, took the reins last year. Pledges to boost competitiveness of local economy by increasing research and technology spending.

DEMOCRATIC PARTY OF SLOVENIAN PENSIONERS (DESUS) - Seven seats. Although left-of-centre, party was a junior partner in Jansa's conservative government but has indicated it would be ready to join the new centre-left coalition. It demands higher pensions and better health care for the elderly. It is headed by Karl Erjavec who was Slovenia's defence minister for the past four years.

(Reporting by Marja Novak in Ljubljana; Editing by Charles Dick)