The 5-Star Movement, led by 31-year-old Luigi Di Maio, has been particularly successful at tapping into the disaffection in the underdeveloped south and has promised a monthly universal wage of up to 780 euros ($960) for the poor.
Sister Vincenza, voting at a polling station on Rome's Aventine hill, said the process was "all mixed up". While the centre-right coalition that capitalized on Italy's anti-migrant sentiment led the polls, analysts predicted the likeliest outcome of Sunday's vote was a hung parliament.
Mr Berlusconi can not stand for office again due to a 2013 tax fraud conviction, however his party is ahead in the polls and he is likely to emerge as a kingmaker.
The campaign itself was marked by neo-fascist rhetoric and anti-migrant violence that culminated in a shooting spree last month against six Africans.
According to recent opinion polls, published in mid-February, former Prime Minister Silvio Berlusconi's right-wing coalition formed by Forza Italia, the anti-immigrant Northern League party and the Brothers of Italy could be the eventual victor with about 35 per cent of the vote, although insufficient to form the government.
"The situation is pretty bad, that is there aren't candidates valid enough".
Official results of Sunday's elections are expected in the early hours of Monday.
Polling stations opened 7:00 a.m. local time and are expected to close at 11:00 p.m. and the exit polls would start rolling out soon after.
If no party wins an overall majority, one scenario outlined by analysts could be a grand coalition between the PD and Forza Italia - a prospect that would reassure investors but risks spreading more cynicism and emboldening populists and the far-right.
The anti-establishment Five Star party was founded in 2009 by comedian Beppe Grillo, who denounced cronyism in Italian politics.
Just which parties coalesce from among the three main blocs - the centre-right coalition, centre-left coalition and the anti-establishment 5-Star Movement - will determine Italy's course.
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They are not all elected at the same time - half are elected in one election, and the other half three years later. Beside him, Faisal Sakhi Butt hailing from Islamabad is also the PPP candidate for Senate in Khyber Pakhtunkhwa.
"I think 5-Star will win. but I'm also anxious that there won't be a victor".
"Five Star Movement is transforming the political landscape", said political science professor Roberto D'Alimonte from Rome's Luiss University.
"This will be the moment of truth", he said.
Democratic Party leader Matteo Renzi told a final campaign event in his native Florence on Friday that only a vote for his party would prevent Salvini from taking power. Gentiloni has been cited as a possible candidate for premier.
Italy elections 2018 Live Updates: Ballots are being prepared for Sunday's general elections as a polling station is being set up in a school in Rome, Saturday, March 3, 2018. If they actually win, other parties can woo them away to beef up their own ranks.
In addition, new anti-fraud measures involved the time-consuming logging of individual ballot serial numbers in voter registry books, and then checking the completed ballot against them to make sure they match.
While European capitals and Brussels were watching the outcome for its effects on policy and markets, some in Italy had more at stake personally.
Berlusconi also said he was concerned about the queues.
"Yes indeed I fear these results because I have arrived here with all my thoughts and dreams", said Musab Badur, an asylum seeker from Sudan who is living in a Milan shelter. "And I never thought that one day maybe I would have to go back".