POLITICAL PARTNERS: Ms Cristina Fernandez de Kirchner and her husband, President Nestor Kirchner, celebrating her win. She will take over the reins of power in December. -- PHOTO: BLOOMBERG

Ms Fernandez, a lawyer and centre-left senator, will take over from President Nestor Kirchner in December in a rare power handover between democratically elected spouses.

Mr Kirchner has not said why he is standing down.

Partial results showed Ms Fernandez with 44per cent support, double that of her nearest rivals and enough to claim victory and avoid a run-off vote.

Her main rivals, former lawmaker Elisa Carrio and former economy minister Roberto Lavagna, both conceded defeat.

'We have won by a large margin,' the 54-year-old senator and mother of two told cheering supporters in a speech broadcast live on TV on Sunday hours after polls closed, as officials worked into the night counting ballots.

With her husband applauding beside her, Ms Fernandez made special mention 'of the man who is at my side today, and who has been my companion all my life'.

Although she was prominent nationally before her husband, many see her presidency as a second Kirchner term.

The two have had a tight political partnership for 30 years and he is expected to be her top adviser, just as she was his.

In the lead-up to the elections - which she entered as the favourite - Ms Fernandez emphasised her spouse's presidential record more than her own two decades as a lawmaker.

Mr Kirchner, 57, enjoys widespread popularity for having overseen an impressive turnaround in Argentina's economy during his four-year term.

When he came in, the country was still struggling after a 2001 economic collapse that saw it become the biggest-ever defaulter of sovereign debt, owing more than US$100billion (S$145 billion). Since then, the economy has grown nearly 50per cent and unemployment has been halved.

Ms Fernandez reminded supporters of that and claimed part of the credit, telling them: 'We have repositioned the country, fought poverty and unemployment, all these tragedies that have hit Argentines.'

Observers, though, said she could be in for a rough ride if she ignored the threats now stalking the country: a rising cost of living, rising crime and low foreign investment.

'She will find it a very different challenge than that during her husband's term,' said Mr Michael Shifter, a Latin American analyst at the Washington think-tank The Dialogue.

Much more comfortable on the diplomatic stage than her travel-shy husband, Ms Fernandez will remain friendly with anti-US President Hugo Chavez of Venezuela while trying to improve relations with the United States.

In electing her, Argentines have opted for continuity, a sign of a deep fear of change after decades on an economic roller coaster that has wiped out life savings time and again.

The bulk of her supporters are poor people who think that Mr Kirchner improved their lives, partly through new pensions and tax breaks.

But top opposition candidate Carrio gave Ms Fernandez a run for her money in middle-class and urban areas like the capital Buenos Aires.

Argentina has had a woman president before, but she was not elected. Isabel Peron, the third wife of former president Juan Peron, succeeded him when he died in 1974 and ruled for two years until she was ousted in a military coup.

Ms Fernandez has been compared to Peron's second wife, the mid-20th-century icon Eva 'Evita' Peron. But she has more in common with US presidential candidate Hillary Clinton, since both are lawyers and senators married to men who were governors and later became presidents.

Ms Fernandez is the fifth elected woman leader in Latin America.

REUTERS, AGENCE FRANCE-PRESSE

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