Italy's eurosceptic and anti-establishment opposition party, the Five Star Movement (M5S), made strong gains in a first round of nationwide local elections, while Prime Minister Matteo Renzi's Democrats (PD) suffered setbacks, results showed Monday.
About 13 million people - a quarter of the electorate - were called to elect new mayors in more than 1,300 municipalities. But the most important race in the Sunday vote was in Rome, where the M5S fielded 37-year-old lawyer Virginia Raggi.
With all votes counted, she led the race at 35.25 per cent, while PD candidate Roberto Giachetti was trailing at 24.9 per cent. Since the 50-per-cent victory threshold was not cleared, a run-off between the top two finishers is due on June 16.
"Ladies and gentlemen, the wind is changing, the wind is changing," Raggi said in overnight comments. "This is only the half time result, there will be a final sprint, but it is a historic moment," she added.
Barring a major upset, Raggi is poised to become Rome's first-ever female mayor and the youngest in at least a century. That would save the M5S leader, comedian Beppe Grillo, from following through with a campaign promise to "set [him]self on fire" in case she did not make it.
Raggi presented herself as a clean broom in a city with broken public services and crippling debt, rattled by a major corruption scandal involving previous administrations which partly contributed to the downfall of outgoing PD mayor Ignazio Marino.
The election outcome suggested that Renzi - battling with banking crises, a stagnant economy and surging migration - is experiencing a midterm slump in popularity, complicating campaigning for another key vote scheduled for October.
The premier said he was "not happy" about Sunday's elections, but insisted that they were a mixed bag for all major parties.
PD candidates had a tough time in other key races: in Turin and Bologna incumbent mayors started out as frontrunners, but were forced into run-offs with conservative or M5S opponents that could produce surprising results in two weeks' time.
But the M5S' success in Rome was tempered by less-than-stellar performances in Naples and Milan, where it won only about 10 per cent of the votes, and by the fact that it ran in only about a fifth of municipalities that held elections.
With voting taking place at the end of a bank holiday weekend, a low turnout was widely expected. Only 62.1 per cent of eligible voters cast their ballots, compared to 67.4 per cent in the previous elections, the Interior Ministry said.