ROME — Five months before an election that will be crucial not just for this country but the whole euro zone, Italy is mired in some of its greatest political uncertainty since World War II. Nobody knows what electoral system will be used or who the candidates will be in a parliamentary poll that will be marked by Italian voter anger over the pain of austerity. The once-dominant party of billionaire media tycoon Silvio Berlusconi risks disintegration while the centre-left Democratic Party (PD), likely winner of the election, is torn by splits sharpened by a challenge to its leader Pier Luigi Bersani by the youthful mayor of Florence, Matteo Renzi. “All election campaigns are marked by uncertainty but this time ... we do not even know what electoral law will be used, who will be the party leaders and what will be the coalitions,” PD official Lapo Pistelli said. “This is something totally new.” Foreign governments and investors want to see a return by respected, unelected technocrat Prime Minister Mario Monti after the poll, but the road to such an outcome is beset by big obstacles which are just as unpredictable as everything else. Corruption scandals across Italy have fanned disgust with politicians and rocketed the anti-establishment, anti-Europe 5-Star Movement led by shaggy-haired Genoese comic Beppe Grillo into second place in opinion polls. Around half of Italians are undecided about how to vote or say they will abstain in the poll expected on April 7-8, thickening a fog of chronic confusion. While most concern about the euro zone currently focuses on Spain and Greece, Italy - the bloc's third largest economy - is not far behind. Italy would race to the forefront if deeper chaos emerges from the election, as looks possible, spooking investors and pushing Rome's borrowing costs to dangerously high levels. Many are comparing the atmosphere now to 20 years ago when the “Clean Hands” corruption investigation overturned the entire system and destroyed the dominant Christian Democrat party. Berlusconi, 76, who was replaced by Monti last November when Italy tottered close to a Greece-style meltdown, added to the chaos at the weekend when he threatened to pull the plug on his successor, who depends on a broad cross-party alliance. Although Angelino Alfano, secretary of Berlusconi's People of Liberty (PDL) party, quickly disowned this threat, the scandal-plagued magnate's outburst after a conviction for tax fraud added to the fevered atmosphere ahead of the vote. If the results of a Sicily regional election last weekend are anything to go by, politicians are right to be worried. Grillo's candidate took most votes, although a left-centrist alliance robbed him of the governorship. More than 50 percent of voters abstained. “The 5-Star Movement could become the biggest party in Italy,” said Roberto Weber, chairman of SWG polling institute as Italy reflects a trend across Europe of disillusionment with conventional political parties. The PDL, which swept every seat in Sicily a decade ago when Berlusconi was in his heyday, won less than 13 percent, hit particularly badly by abstentions. But 40 percent of Grillo's votes came from former centre-left supporters, SWG said, and senior PD official Pistelli told Reuters they were worried by the comic's success and by the steep decline of the PDL as the other main established party. No single government out of the more than 60 since World War Two has lasted a full five-year term but politicians, academics and diplomats say they cannot recall a similar confluence of economic and political crisis. Angry Italians, like other southern Europeans, are suffering badly in a deep recession worsened by Monti's debt-cutting measures. “The economy is by far the dominant issue. After years of crisis, 2012 was even worse and households are starting to feel the pinch with more and more people out of work,” said SWG vice president Maurizio Pessato. “I do not believe there has ever been such a dramatic combination of institutional confusion and economic crisis for Italian families,” said a parliamentarian close to Berlusconi who asked not to be named. “This cocktail is really explosive.” Monti is not standing as a candidate in the election, which would make it very difficult for him to become prime minister under the existing electoral law, and there is strong opposition to the idea both from the public and inside the center-left PD.— Reuters