Results a blow to PD secretary Renzi as he struggles to reunite party.
The centre right scored a clear victory in local election run-offs across Italy on 25 June, taking almost all of the 22 regional or provincial capitals where the mayorship was up for grabs.
These included the Liguran regional capital of Genoa, traditionally a stronghold of the centre left, where centre-right candidate Marco Bucci won over his centre-left rival Gianni Crivello.
The centre right, which presented a largely united front comprising Silvio Berlusconi's Forza Italia (FI), the anti-migrant Northern League (LN) and the right-wing Brothers of Italy (FdI) party, also took the traditionally ‘red’ cities of Pistoia and La Spezia, among others.
In L’Aquila the results of the first round were overturned, with centre-right candidate Pierluigi Biondi winning over his centre-left competitor Americo Di Benedetto. The candidates had polled respectively 35.9 per cent and 47 per cent on 11 June.
The anti-establishment 5-Star Movement (M5S) was largely absent from the run-off after performing badly in the first round.
Federico Pizzarotti, a former M5S member, was re-elected as mayor of Parma over centre-left candidate Paolo Scarpa on the civic list Effetto Parma.
Centre-right leaders hailed the results as a boost to political alliances on national level ahead of general elections, which will be held at the latest in February next year. During the current parliament parties on the centre right have struggled to find a common voice.
The results instead came as a blow to recently re-elected Partito Democratico secretary Matteo Renzi, who is trying to reunite the party after a long season of internal dissent sparked largely by his own policies when he was prime minister.
Overall voter turnout in the run off was 46.03 per cent, compared to 60.07 per cent at the first round.