ROME - Italians began voting on Sunday in one of the most closely watched elections in years, with markets nervous about whether it will produce a strong government to pull Italy out of recession and help resolve the euro zone debt crisis. 

A huge final rally by anti-establishment-comedian-turned-politician Beppe Grillo on Friday before a campaigning ban kicked in has highlighted public anger at traditional parties and added to uncertainty about the election outcome. 

Voters started casting their ballots at 7 a.m. (1 a.m. ET). Polling booths will remain open until 9 p.m. (4 p.m. ET) on Sunday and between 6 a.m. and 2 p.m. (midnight and 10 a.m. ET) on Monday. Exit polls will come out soon after voting ends and official results are expected by early Tuesday. 

The election is being followed closely by financial markets with memories still fresh of the potentially catastrophic debt crisis that brought technocrat Prime Minister Mario Monti to power more than a year ago. 

Italy, the euro zone's third-largest economy, is stuck in deep recession, struggling under a public debt burden second only to Greece's in the 17-member currency bloc and with a public weary of more than a year of harsh austerity policies. 

Economic austerity has fueled anger among Italians grappling with rising unemployment and shrinking disposable incomes, encouraging many to turn to Grillo, who has tapped into a national mood of disenchantment. 

Final polls published two weeks ago showed center-left leader Pier Luigi Bersani with a 5-point lead, but analysts disagree about whether he will be able to form a stable majority that can push though the economic reforms Italy needs. 

Bersani is now thought to be just a few points ahead of center-right rival Silvio Berlusconi, the four-times prime minister who has promised tax refunds and staged a media blitz in an attempt to win back voters. 

Berlusconi criticism 
Berlusconi hogged the headlines on Sunday after he broke the campaign silence the previous evening attack magistrates, saying they were "more dangerous than the Sicilian mafia" and had invented allegations he held sex parties to discredit him. 

The 76-year-old billionaire, who faces several trials on charges ranging from fraud to sex with an underage prostitute, was criticized by his election rivals for making the comments after the campaigning ban had come into force. 

While the center left is still expected to gain control of the lower house, thanks to rules that guarantee a strong majority to whichever party wins the most votes nationally, a much closer battle will be fought in the Senate, which any government also needs to control to be able to pass laws. 

Seats in the upper house are awarded on a region-by-region basis, meaning that support in key regions can decisively influence the overall result. 

Pollsters still believe the most likely outcome is a center-left government headed by Bersani and possibly backed by Monti, who is leading a centrist coalition. 

But strong campaigning by Berlusconi and the fiery Grillo, who has drawn tens of thousands to his election rallies, have thrown the election wide open, causing concern that there may be no clear winner. 

Surveys have shown up to 5 million voters are expected to make up their minds at the last minute, adding to uncertainty. 

Italy's Interior Ministry urged some 47 million eligible voters to not let bad weather forecasts put them off, and said it was prepared to handle snowy conditions in some northern regions to ensure everyone had a chance to vote. 

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