Arbau, a member of the Democratic Party, asked a primary election for the presidency of the Province of Nuoro.
The regional section of the PD was also divided on the case: MPs Antonello Soro, Gian Piero Scanu, Guido Melis and Caterina Pes supported Arbau, and regional councillor Francesca Barracciu described the expulsion of Arbau as a "squad and Holy Inquisition method".
[2] In 2013 Arbau took over the seat in the Regional Council from Barriacciu, who had been elected to the European Parliament, and joined the Sardinia is already Tomorrow group.
[3] However, Arbau left the group shortly after, in dissent with the chairman Mario Diana on the request for a secret vote on the amendment to the double preference, thus causing its dissolution.
[4] In the 2014 regional election, The Base took part in the centre-left coalition in support of Francesco Pigliaru's candidacy, which later turned out to be a winner.