Silvio Berlusconi has reportedly threatened to withdraw his Forza Italia party from Italy’s governing majority if the current prime minister, Mario Draghi, is elected president later this month. The scandal-tainted media tycoon, who served four times as prime minister, is in Rome from Tuesday on the hunt for votes as he ramps up his own presidential campaign. The secret ballot by more than 1,000 parliamentarians and regional representatives begins on 24 January and is expected to go through several rounds before a successor to Sergio Mattarella, who steps down on 3 February, is elected. There are no official candidates in Italy’s presidential elections, although party leaders usually try to agree on a candidate. Berlusconi, 85, is a favourite among the rightwing parties for the seven-year-mandate. However, Draghi, who is credited with restoring stability in Italy, as well as keeping the broad coalition in line, is tipped as the frontrunner. According to reports in the Italian press, Berlusconi said that without Draghi as prime minister, “Forza Italia would leave the majority”. Draghi’s potential promotion risks bringing general elections forward by a year. In a poll released on Tuesday, more than 50% of Italians said Draghi was the person most fit for the job, while 39% supported Berlusconi. Berlusconi, who was temporarily banned from public office after a tax fraud conviction in 2013 and is still being tried for allegedly bribing witnesses in an underage prostitution case connected to his notorious “bunga bunga” sex parties, has reportedly been bombarding parliamentarians in the lead-up to the ballot in what the Italian press has described as his “Operation Squirrel campaign”. Antonio Tajani, the deputy Forza Italia leader, said Draghi needed to remain prime minister and that with Berlusconi as president, “the government would be solid”. Draghi hinted in December he would be prepared to accept the role if elected. However, he began a press conference on Monday night by vetoing questions about the presidential race. “Only Draghi can do this [prime minister] job,” Tajani told La Stampa. “Without Draghi it’s impossible to have a unity government … we’re participating in this government because of Draghi.” Tajani said Forza Italia’s withdrawal from government would be inevitable if Draghi moved to the presidential palace. “The majority would implode,” he said. Italy’s president has a largely ceremonial role, albeit with the power to resolve political crises, pick prime ministers and call early elections. Mattarella was forced to step several times to resolve crises, including calling on Draghi to form a unity government last February after the administration led by Giuseppe Conte collapsed. Analysts believe Berlusconi will struggle to garner enough support for his bid, even if he is noted for his shrewd “vote-buying skills”. On the eve of his campaign, he posted a photo of himself and his girlfriend, Marta Fascina, a Forza Italia politician, on Instagram, alongside the message: “Happy birthday.” Fascina turned 32 on Sunday.