BUENOS AIRES, Argentina (Reuters):

First lady Cristina Fernandez de Kirchner declared victory in Argentina's presidential vote yesterday and was set to become the first woman elected to lead the country.

"We've won by a wide margin," she told followers in a speech at her campaign bunker as exit polls and early official results showed her with enough support to take a first-round victory and avoid a run-off election next month.

Cheers and applause erupted at Fernandez's campaign bunker and dozens of supporters banged drums outside when television channels flashed the exit poll numbers.

"She is going to be the same as her husband, who has done a lot of things like build houses for the poor," said 50-year-old chauffeur Ramon Reggie Quiroga.

With 15 per cent of polling stations counted, Fernandez had 42.4 percent of the vote, followed by former Economy Minister Roberto Lavagna with 21.2 per cent and former lawmaker Elisa Carrio with 18.6 per cent.

Television exit polls showed Fernandez, a centre-leftist senator, with 42 per cent to 46 per cent support, and Carrio in second place.

To avoid a run-off, Fernandez needs more than 45 per cent of the vote, or 40 per cent with a 10 percentage-point lead over the nearest rival.

The early official results were not representative, the Interior Minister said, because they did not include the most populous areas of the country.

Fernandez, 54, ran on the record of her husband, leftist President Nestor Kirchner, and she would take over from him in a highly unusual transfer of power between democratically elected spouses.

Many Argentines credit Kirchner with pulling the country out of a dramatic economic crisis in 2001-02 and using growth of eight per cent a year to create jobs, raise salaries and expand pension benefits.