Certainly, Grillo has shown no willingness to cooperate with existing parties, and many of his candidates lack political experience — which the movement’s supporters consider to be an advantage.
Grillo is the top pick among first-time voters who find in him an expression for their rebellion. He is also picking up support from disaffected backers of the populist Northern League, who are unhappy that their leaders teamed up with Berlusconi.
It is unclear how many of the 30 percent of Italy’s undecided voters will throw in their lot with the comic. Mannheimer believes they will be many.
Grillo’s campaign to upend Italian politics is anything but routine.
In a nation where the people get most of their information from television — dominated in part by Berlusconi’s media empire — Grillo eschews TV, a medium that shunned him for years, and forbids candidates running under his banner from appearing on air at the risk of being booted from the movement.
He seeks more direct contact with his followers, in piazzas and through his blog, one of the most popular in Italy. He approaches his public appearances as he does his stadium comedy routines: He speaks and the audience listens. The one-way flow has led to criticism that he refuses to engage in debates about his ideas with opponents or even supporters — though that has done little to stem his rise.
‘‘However it goes, and whoever wins, this will be remembered as the elections of Beppe Grillo,’’ columnist Beppe Severgnini wrote in Corriere della Sera on Thursday.