BUENOS AIRES—The Argentine peso currency crashed following news that populist left-wing Peronist opposition leader Alberto Fernández was leading in the primary election.
Market fears over Argentina’s potential return to the interventionist economics of the previous leftist government prompted stocks and bonds to tumble, and Argentines rushing to buy U.S. dollars. In response, President Mauricio Macri vowed on Aug. 12 that he would win a second term.