Luigi Di Maio is the moderate face considered most likely to succeed in turning 5-Star into a party that could govern Italy | Andreas Solar/AFP via Getty Images Millennial who wants to oust Matteo Renzi The 5-Star Movement’s Luigi Di Maio is targeting Rome and Naples — with an eye on national success.

MILAN — Luigi Di Maio is a young man in a hurry: The 29-year-old wants to turn Italy’s 5-Star Movement into a grown-up party that can challenge Matteo Renzi’s Democratic Party (PD) on the national stage, if it can first prove its mettle in local elections in Rome and Naples.

Di Maio prefers to put it the other way round, and ask if Renzi’s PD is ready for the 5-Stars.

Judging by the opinion polls, it is not an empty boast: The anti-establishment movement set up by comedian Beppe Grillo in 2013 looks ready to pose a formidable challenge to the PD in Rome and Naples between April and June. And Di Maio is second only to Renzi in popularity nationwide.

"I am just a voice among thousands," the Neapolitan politician said in an interview, paying lip service to the Movement’s anti-authoritarian roots and its dislike of traditional political structures.

But since Grillo once joked "Damn you, you are the leader,” Di Maio has become the moderate face of the M5S, and the man considered most likely to succeed in turning it into a party that could govern Italy.

According to a February poll by Ixè, the 5-Star Movement is snapping at the PD's heels with 24.9 percent support versus 33.3 percent for the prime minister's center-left PD. However, according to another poll by Istituto Piepoli, if the 5-Stars and PD were to face off in a second round of elections, the 5-Stars would attract enough center-right votes to win by 55.2 percent to 47.8 percent.

One thing is certain: we want to win and double our members working within the institutions.” — Luigi Di Maio

It polls well at a national level, but the Movement is projected to perform even better on the local level when Rome and Naples — Italy’s first and third largest cities respectively — hold their municipal elections in the next few months. There's s a good chance it could win both contests.

In Rome, the 5-Star candidate, Virginia Raggi, has 33 percent support and a strong chance of winning the ancient Campidoglio town hall, partly because the PD is reeling from the “Mafia Capitale” corruption scandal that linked municipal officials with organized crime. In Naples, the party scores 24 percent of voter preferences and also could win.

“One thing is certain: we want to win and double our members working within the institutions,” Di Maio said.

If the 5-Stars managed to win even one of those two cities — and Di Maio believes they will — the movement would face its most important governmental challenge yet, one that would come with high hopes and expectations from a party base that, according to polls, is “ready to govern.”

The few 5-Star mayors who have managed to win local elections offer mixed track records.

The Tuscan port town of Livorno, the second most important town governed by the 5-Stars, led by grillino — the nickname for Grillo followers — Filippo Nogarin, cut 4 percent of social spending and increased taxes on trash since it took office in June 2014.

In Parma, a rich city in Italy’s north as well as the most important town hall currently under 5-Star rule, the mayor won in 2012 by claiming he would shut down the local incinerator, a promise he has yet to fulfill.

There are 16 town halls under 5-Star rule, including Ragusa in Sicily and Sarego in the Veneto region, the first town to elect a grillino as mayor.

Budget problems and cuts to welfare are affecting the work of most Italian mayors. The problem — and the one the 5-Star leadership fears it will have to confront if it does take control of Rome and Naples — is when the high expectations built on three years of promises clash with the realpolitik of everyday compromise.

Grillino of the first hour

Founded by Grillo to challenge what he calls Italy’s “gerontocracy,” the MoVimento 5 Stelle is not immune to the vices of Italian politics.

In a town near Di Maio's Naples base, the mayor was involved in a scandal involving organized crime last December. The party's diverse social base was also confused by the national leadership's contradictory positions on same-sex marriages in a parliamentary vote last February, when it opposed Renzi's progressive reforms for procedural reasons.

Before those two setbacks, Di Maio was the most popular political leader in the country. At present, he is the favorite of 24 percent of Italians, ranking him before Grillo and behind Renzi.

Other party heavyweights, such as Alessandro Di Battista and Roberto Fico, are way behind in the popularity stakes — Di Battista with 13 percent backing among 5-Star supporters and Fico, who holds the influential position of president of public broadcaster RAI’s supervisory committee, on 5 percent.

In contrast to the movement’s rambunctious leader, Di Maio is known for his sober and meticulous style.

“Di Maio is the one able to parliamentarize the movement,” said Tommaso Cerno, one of Italy’s leading experts on the 5-Stars. “He is a grillino of the first hour — an element that creates a bond between yesterday’s and today’s supporters — as well as being the moderate face who can attract voters from other parties, especially the center-right.”

In contrast to the movement’s rambunctious leader, Di Maio is known for his sober and meticulous style, as well as his ever-present dark blue suits and crisp white shirts.

The oldest of three brothers, Di Maio got started on political activism in high school in Pomigliano D'Arco, a town near Naples, where the movement's current candidate, Dario De Falco, recalls the two of them standing for the student body, founding a student organization and then getting involved in local politics.

“He has always been primarily interested in being popular among his peers," said Tommaso Ederoclite, a former university classmate. "He didn’t come to class very often and his grades were not that good. And I bet that’s why he decided to drop out in the end.”

Valeria Ciarambino, who now sits on the council of Campania, the region surrounding Naples, recalled first meeting Di Maio on a campaign to prevent a local park in Pomigliano D’Arco from being paved over for a parking lot. "We worked together almost every day and I was struck by his talent and willingness to relentlessly scrutinize hundreds of pages of public records,” she said.

They saved the park, but Di Maio didn't reap the political dividends when he ran in local elections in Pomgliano in 2010 and got only 59 votes. Even his own father, a long-term militant of the far-right MSI, didn’t vote for him.

Conspiracy to make us win

Di Maio's big break came in 2013, when the party held online primaries which were a huge novelty in Italian politics at the time, just 189 votes landed him the post of vice president of Italy's Chamber of Deputies. At 26, he was the youngest person ever to do that job. He made up for his lack of experience with exceptional rigor, to the point where one veteran MP said Di Maio was "the strictest president of the Chamber of Deputies I have ever known. I bet he learned the code of conduct by heart.”

Yet the rise wasn’t without tensions.

Political talk-shows now fight each other to book the MoVimento's de facto leader as a guest.

Sebastiano Barbanti, a former 5-Star MP who now sits as an independent, told POLITICO he was very disappointed with Di Maio, because in his view the vice president “can’t have an institutional role and be on TV all the time. When the MoVimento was born it was about ‘one is equal to one’ — an element that has disappeared in today’s party.”

The criticism seems to bounce off him. Political talk-shows now fight each other to book the MoVimento's de facto leader as a guest, newspapers compete to interview him and if the 5-Stars were to win national elections, Di Maio is the person most likely to be chosen as prime minister — if, that is, the party really wants to run the country or some of its benighted cities, including the capital.

Di Maio has repeatedly said the party "will form no coalitions with those who have destroyed the country," which is sometimes taken as meaning the party feels more vocation for the confrontational powers of opposition than the scrutiny of government.

"In Rome there is a conspiracy to force us to win," said Paola Taverna, one of the movement's Roman leaders, last month. The city is running a vast budget deficit approaching €1 billion, hindering its capacity to fix problems from public transport to waste management and city planning which mayor after mayor has proved unable to solve.

Echoing Di Maio’s remarks on his distaste for coalitions, the Rome senator’s comments suggest the party leadership doubts it can deliver on its promises of radical change in a notoriously ungovernable city, and believes itself better suited to the watchdog role, avoiding direct responsibility.