By Gavin Jones
ROME (Reuters) - Forget the outbursts of Beppe Grillo. To gauge the prospects of the anti-establishment 5-Star Movement listen out for the more measured tones of 29-year-old Luigi Di Maio, fast emerging as the next leader of Italy's second largest party.
The 5-Star Movement exploded onto the scene at Italy's 2013 national election when it won a stunning 25 percent of the vote, paving the way for the rise of anti-system parties around Europe, such as Podemos in Spain and Syriza in Greece.
When most people think of 5-Star they still think of Grillo, the burly, shaggy-haired comedian who founded the movement six years ago. But over the last year the 67-year-old maverick has been gradually handing over the reins to a new "directorate" of five young leaders.
Without any formal investiture Di Maio has become by far the most prominent of these, and he is widely expected to be the party's candidate for prime minister at the next election.
That is due in 2018, but with Prime Minister Matteo Renzi facing growing divisions in his parliamentary majority, many commentators believe the vote might come much sooner.
"Damn it, you're the leader now aren't you," a chuckling Grillo told Di Maio this week at a joint news conference. "I'm not in the picture any more," he added.
In line with its credo of direct democracy, the leader and candidate for premier will be formally chosen ahead of the election by an on-line ballot of 5-Star's members.
"We made big mistakes after the 2013 vote but we have learned from them," Di Maio told Reuters in the enormous office he occupies as deputy speaker of the Chamber of Deputies, his slight figure dwarfed by gilt baroque mirrors and renaissance paintings. "We spent all our time trying to get organized and we didn't communicate with the outside world."
Unlike Podemos and Syriza on the left, or France's National Front and the United Kingdom Independence Party on the right, 5-Star rejects ideological labeling and draws support from both sides of the political divide, especially among the young.
Far from collapsing without Grillo's front-line role, as was widely expected, it is continuing to consolidate and grow while the popularity of Renzi and his Democratic Party (PD) declines.
Five-Star's proposals include a referendum on Italy's euro membership, universal income support for the poor, tax cuts for small businesses, and state run banks to fund investments in new technologies, renewable energy and high-quality agriculture.
These resonate with millions of Italians hard hit by years of economic decline, but pollsters say its image as the only "clean" party is just as important for its success. It has been immune from the corruption scandals that continue to tarnish the PD and other parties.
It eschews state financing and its parliamentarians pay a large part of their monthly salaries into a fund to finance small businesses. Di Maio says he gives up almost two-thirds of the 15,000 euros ($17,000) he could take home every month as a parliamentarian and deputy speaker of the Chamber.
NARROWING THE GAP
Opinion polls show the PD is still the country's largest party, but the lead over 5-Star has now narrowed from around 20 points a year ago to between six and 10. Some polls put 5-Star as high as 26 percent, its highest ever level and about 10 points ahead the anti-immigrant Northern League in third place.
A survey this week by the Piepoli institute said in a head-to-head with Renzi, Di Maio, despite his still far lower media profile, would take 46 percent of the vote, more than any other opposition politician.
Di Maio could hardly be more different from Grillo. He is clean-shaven, soft-spoken and always keeps his calm. He is often called 5-Star's "institutional" face, reflecting both his preference for dark jackets and ties, and his role as lower house vice president.
After refusing to co-operate with mainstream parties to break the political deadlock when the 2013 election produced no clear winner, 5-Star's ratings fell, internal divisions grew and 20 percent of its parliamentarians defected.
When Renzi eventually took power in 2014 following an internal power struggle in the PD and won a record 41 percent of the vote at European elections in May that year, many commentators expected the movement quickly to collapse.
"We are still angry at the system, but we realized that has to be communicated in a different way, now we never talk about us, we only talk about our proposals," Di Maio said, adding that he had no illusions about the obstacles to winning power.
"A lot of people are still afraid of us," he said. "Of course we will change things if we win, but we have to reassure people there won't be any kind of violent revolution."
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(Editing by Crispian Balmer and Anna Willard)