Almost complete Italian mayoral election results confirm that voters have rejected populist candidates.
The anti-euro party hopes to build momentum with the vote, which comes before a national election that must be called in less than a year.
Exit polls indicated the 5-Stars' hopes to make inroads in the south also would be dashed.
The collapse of that accord seems to have reduced the chances of a snap election in the autumn, but the broad coalition backing Prime Minister Paolo Gentiloni is fragile and analysts say an early vote still can not be ruled out.
"They do not make choices, they don't make decisions, or assume their responsibilities".
Italy's anti-establishment 5-Star Movement (M5S) is in disarray following a disastrous start to its rule in Rome city hall, potentially denting its chances of winning power at a national level.
Yet the movement only managed to attain 20% of the vote or less in most of the main cities, which stood in stark contrast to the strong victories scored in Rome and Turin in May past year.
In all but one of the top cities up for grabs, candidates from centre-right and centre-left alliances earned berths in June 25 run-offs, since none clinched more than 50% of the votes.
Leoluca Orlando, a center-left figure who made his name as an anti-Mafia maverick in the 1980s, is running for a fifth mandate as mayor of Palermo, Sicily, a stiff challenge for the 5-Stars.
The final local election results, where voters choose mayors and councillors in more than 1,000 towns and cities, will be decided in a second round of voting in two weeks' time.
The political climate ahead of the vote became even more hostile this week after a deal on electoral reform among the main parties broke down in parliament amid bitter recriminations.
The collapse of that accord seems to have reduced the chances of a snap election in the autumn but the broad coalition backing Prime Minister Paolo Gentiloni is fragile and analysts say an early contest still can not be ruled out.
The ruling Democratic Party and the Five Star had been neck-and-neck in national opinion polls, with each drawing about 30 percent support.
In the northern city of Parma its first ever mayor, elected in 2012, ran as an independent after falling out with the party leadership a year ago.
Most of the 5-Star candidates would have been new to government.