Cristina Fernández de Kirchner of the Buenos Aires province, both leaders had their respective wives run for the office: Hilda González de Duhalde for the PJ, and Cristina Kirchner for the Front for Victory. Cristina Kirchner won the election. The presidential election was held on 28 October 2007. With Kirchner leading all the pre-election polls by a wide margin, her challengers focused on forcing her into a ballotage. To win in a single round, a presidential candidate in Argentina needs either more than 45% of the vote, or 40% of the vote and a lead of more than 10 percentage points over the runner-up.
Cristina Fernández de Kirchner opted instead to send a bill to Congress for the renationalization of YPF, privatized in 1993, blaming the Spanish company Repsol for the energy trade deficit. The bill was approved by the Chamber of Deputies by a 207-32 margin. It was criticized as an authoritarian move, as there was no negotiation with Repsol. As well, the Vaca Muerta oil field had been discovered by this time. However, YPF was unable to afford the costs to exploit the oil at the site, and the rights to drill at Vaca Muerta were sold to the Chevron Corporation. The costs of energy imports