Italy’s insurgent Five Star Movement will be well placed to make a bid for power after its bitter grass-roots campaign against Matteo Renzi’s constitutional reforms gave it renewed electoral momentum, experts warned on Sunday night.

The populist movement founded by Beppe Grillo, a stand-up comedian from Genoa, has been at the forefront of a three-month campaign that has stirred up the deep economic and social divisions in Italian society.

Closing the movement’s 48-stop nationwide tour in Turin last weekend, Mr Grillo fulminated against Italy’s ruling elite, which has come to be typified by the youthful figure of Mr Renzi who has staked his political future on winning the referendum and holding the political centre ground.

"I believe that whatever the response, we have decided we want to go to elections," Mr Grillo said after casting his vote in his home town of Nervi, just outside Genoa.

He said the Five Star Movement, which fishes from both the Right and the Left for the votes of Italy’s disgruntled citizens, would not be daunted, even if Mr Renzi won his referendum.

“If we lose, I will be happy to lose, because I was born a loser, we need to get used to being losers, because the whole world is against us. Who cares if we lose?” he said in the campaign's closing rally.