Kirchner is a key figure in oil and gas policy for Argentina, with her administration nationalising top producer YPF last year.
The president had aimed to increase energy investment with heavy state involvement, but critics have portrayed the approach as interventionist, arbitrary and making it difficult for foreign companies to do business.
A new president could usher in a new energy policy for the country, estimated to have the world's second-largest shale gas reserves and fourth largest oil reserves, according to the US Energy Administration.
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