"I am the best alternative," Costa Rica's first female president Laura Chinchilla said during the election when asked why voters should choose her over her male competitors in Sunday's balloting, dpa reported. The differences between the 50-year-old and her nearest rival, Otton Solis of the Citizen's Action Party, were not always clear. But Chinchilla came out with more than 46 per cent of the vote, making her the Central American country's first female leader. "I want to thank the pioneering women who years ago opened the doors of politics in Costa Rica," Laura Chinchilla told supporters Sunday. "My government will be open to all Costa Ricans of good faith." She has pledged to fight crime, strengthen the police and increase prosperity. Towards the end of the campaign, it was unclear whether Chinchilla - of outgoing President Oscar Arias' National Liberation Party (PLN) - would be able to clear the 40-per-cent hurdle needed for a clear victory without a runoff. Analysts speculated that she would not be able to overcome a united opposition in a runoff campaign. The political scientist is the mother of one son and the wife of Spanish businessman Jose Maria Rico. Her political career began in the 1990s, when she served as acting security minister from 1994 to 1996. Since 2002, she has been a member of parliament and in 2006 Arias named her his vice president. Chinchilla has promised to fight for the poor and weak in her nation, in particular by bringing Costa Rica out of its economic downturn.