The coalition is largely made up of members of the Radical Civic Union, a group of smaller parties and dissident Socialist Party members who support the governing Peronists led by President Cristina Fernández de Kirchner.
Having been expelled from the Radicals, he set up his own party, which eventually settled on the name ConFe (Federal Consensus).
Other leading members of the concertation, often termed 'Radicales K', are governors Miguel Saiz, Gerardo Zamora and Arturo Colombi and deputies such as Hugo Nelson Prieto.
This 'normalization' of Peronist politics left some Kirchner supporters outside Justicialist ranks uneasy, in addition to the government's tough line in the conflict with the agricultural sector.
Some elements of the coalition began to peel away, notably Cobos, who used his casting vote against the moves in the agricultural sector in the Senate and has since been shunned by the Kirchners.