On December 4, Italy faces a referendum that could sink the present government and usher in a new populist era, an outcome made more probable by Donald Trump’s recent election victory in the U.S.

“The U.S. elections have shown that a wind of change is blowing across both sides of the Atlantic and will soon wipe [Prime Minister] Renzi away. His time is over and Italy needs a new government,” said Massimiliano Fedriga, Lower House leader of the conservative Northern League party.

On Thursday, Prime Minister Matteo Renzi renewed his vow to step down if the upcoming referendum fails to pass. “If the citizens vote no and want a decrepit system that does not work, I will not be the one to deal with other parties for a caretaker government,” Renzi said.

At the same time, the Prime Minister reiterated his optimism for the referendum’s success, noting that the largest bloc at the moment are the undecideds, who comprise some 37 percent of the voting population. “For me the silent majority will vote Yes,” he said, which would eliminate the need for talk about a transitional government or parliamentary elections.

Despite Renzi’s hopefulness, recent polls suggest that the referendum is headed for defeat, which means that the Italian president, Sergio Mattarella, would have to name the head of an interim government, to be in place until new elections were held.

Either way, says Renzi, a “no” vote doesn’t mean “Armageddon.” We will simply find ourselves with “enormous regional repayments and one of the most numerous Parliaments in history,” he said.

Few doubt that some sort of reform of Italy’s present political arrangement is necessary. The current system was adopted in 1946 in the wake of the Mussolini dictatorship, and was designed to spread decision-making as broadly as possible. The result was political ineffectiveness and 63 governments since the end of the Italian monarchy.

One of Renzi’s tasks on taking office in 2014 was to streamline Italy’s notorious bureaucracy. Renzi promised reforms aimed at making Italy more governable by significantly shifting the scope and power of the Senate toward the lower house, the Chamber of Deputies. The Senate would be substantially reduced in number and transformed into a “Senate of Regions,” with 100 senators made up mostly of regional councilors and mayors. Meanwhile, power would also be taken away from Italy’s regions and centralized in Rome.

Whether or not this is the best way to reform Italy’s political system may prove irrelevant. Recent polls show that few Italians (one in five) actually understand what the referendum is about, which only serves to reduce the Dec. 4 vote to a thumbs-up or thumbs-down to the Renzi government itself.

Tying his own permanence in office to the success of the referendum on constitutional reform may turn out to be the worst decision Matteo Renzi ever made. His personal popularity has fallen in the wake of a migrant crisis that shows little signs of abating along with growing dissatisfaction with Italy’s participation in the European Union.

On the national level, Renzi’s Democratic party (PD) is now barely ahead of the populist Five Star Movement (M5S), a Eurosceptic party founded by comedian Beppe Grillo that rejects what it sees as a corrupt political establishment.

In June, the M5S saw significant victories in a number of important mayoral elections across the country, including Rome and Turin, wresting power from the ruling PD and galvanizing the young movement’s position as Italy’s leading opposition party.

Grillo’s M5S isn’t alone in opposing the Renzi referendum, however. Most of what remains of media magnate Silvio Berlusconi’s party, Forza Italia, will vote “no” on Dec. 4, as will the populist Northern League party.

Though hardly in alliance with each other, these parties share a common political foe in Matteo Renzi, which doesn’t bode well for the success of Renzi’s referendum—or his government.

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