ROME, March 3, 2018 (News agencies) - Italians are preparing to vote Sunday in an election that pits several shades of populists against the mainstream and which may only succeed in further clouding the political landscape. The anti-establishment Five Star Movement was on track to be the biggest single party when a polling blackout began on Feb. 17, though only Silvio Berlusconi's center-right coalition was within reach of an outright majority. The 81-year-old media mogul has engineered a shock comeback, but only by joining forces with another populist group, the euroskeptic League, which is challenging his dominance of the Italian right. The most likely outcome is a hung parliament, which would trigger an extended period of horsetrading among the parties. Five Star leader Luigi Di Maio, 31, has vowed not to seek a coalition deal, but appealed to rivals to back him if his party wins the most votes. “Five Star Movement is transforming the political landscape,” said Roberto D'Alimonte, a political science professor at Rome's Luiss University. “If the center-right doesn't get a majority, a lot will depend on whether Five Star opens up to the idea of a coalition.” Last year French President Emmanuel Macron and Dutch Prime Minister Mark Rutte held off the challenge of euroskeptic populists in national elections and Chancellor Angela Merkel's party remained the biggest force in the German parliament despite the rise of the anti-immigrant AfD. Italy's establishment parties are struggling to match that performance following years of lackluster growth and widespread concern about immigration. President Sergio Mattarella is due to begin formal discussions with party leaders from early April before picking a candidate he believes can command a majority. The next prime minister will have to win votes of confidence in both houses of parliament. A government built around either Berlusconi's alliance or Five Star would risk unsettling financial markets, with concerns over their impact on state finances in a country with huge public debt. Berlusconi and his allies clashed repeatedly during the campaign over who should be premier and over policies from tax cuts to pension reform and the euro. Berlusconi is banned from holding public office until next year because of a 2013 tax fraud conviction. But he says he could play a key role from the sidelines and has flagged European Parliament head Antonio Tajani as his candidate for the premiership. It's fundamental that the next government “have a premier that has solid relationships in Europe because Italy must regain the influence it's lost in the European Union,” Berlusconi told Italian daily Il Messaggero in an interview published on Saturday Di Maio has unveiled a team of would-be ministers with no government experience and pledged to boost spending on the poor, lower taxes and reduce the public debt -- while also overhauling European Union treaties to ease spending rules. He's backtracked on earlier plans to ditch the single currency, telling Radio 24 on Friday that “euro-exit is not under discussion.”