TOM HENNIGAN
In São Paulo
In the context of Argentina 's no-holds-barred domestic politics, the election of Cardinal Jorge Bergoglio to the papacy presents a challenge to the president, Cristina Kirchner.
While he was archbishop of Buenos Aires the two clashed bitterly, Ms Kirchner comparing his criticisms of her administration to the Inquisition.
But the elation in Argentina at one of their own becoming pope has forced her government into a new approach.
Remarkable U-turn
The president's Peronist movement has, in less than a week, executed a remarkable U-turn and is now claiming Pope Francis as one of its own. The president led a huge delegation to his first public Mass at the Vatican, while back home, her loyalists are quickly rewriting history.
Over the weekend Buenos Aires was plastered with posters of Pope Francis, with the slogan “Argentinian and Peronist”. Secretary of internal trade and Kirchner loyalist Guillermo Moreno is suspected of being behind the blitz.
Meanwhile, Gabriel Mariotto, vice-governor of Buenos Aires province and another key ally of Ms Kirchner, celebrated the election, telling a local radio station that "beyond the nuances and differences, Bergoglio is a great Peronist".
'A Peronist and a comrade'
Emilio Pérsico, a leader of the pro-Kirchner Peronist militant group Movimiento Evita, also appeared in the media calling Francis "a Peronist and a comrade" and claimed he had celebrated a "secret" Mass to pray for the health of recently deceased Venezuelan president Hugo Chávez.
But others condemned the campaign. Horacio González, the director of Argentina’s national library and one of Kirchner’s leading intellectual backers, told a meeting: “It cannot be that our comrades enter into this fraud” calling the campaign “a transcendent backward political step”.