BUENOS AIRES, Argentina (AP) — With a message of unity, former Argentine President Cristina Fernández and running mate Alberto Fernández kicked off their election campaign almost a week after the ex-leader stunned the country by saying she was running for vice president.

Many thought Cristina Fernández, who governed Argentina from 2007 to 2015, would head any presidential ticket and the news that she would play the undercard to her and her late husband's one-time Cabinet chief came as a surprise. The ex-president was seen as the main challenger to President Mauricio Macri.

"I felt obliged to do this," Cristina Fernández said to thousands of supporters ia a poor area in western Buenos Aires.

Fernández's decision to only run as vice president has put a more moderate challenger at the helm of the Unidad Ciudadana ticket.