The reaction in the chamber after the final tally was striking - complete silence.

"I think we are at a crossroads today," said Senator Pier Ferdinando Casini, who has previously supported Berlusconi, in the run-up to the voting.

"However it goes, a 20-year period is concluded."

Berlusconi's removal from the Senate means that he is without elective office for the first time in about two decades and has lost the special immunities given to lawmakers. With other legal cases under way against him, he is now far more vulnerable than he was when, as prime minister, he seemed virtually untouchable, swatting away sex and corruption scandals.

He is soon expected to start performing community service for the tax fraud conviction that formed the basis for his removal from the Senate.

A court in Milan has also ruled that he cannot seek any public office for the next two years.

Determined to show his political viability, defiant Berlusconi bussed in supporters from around Italy for the rally outside his palace in central Rome. They waved flags and sang songs hailing him.

Alessandra Abbate, 49, a supporter from Bologna, said: "It's unfair that they condemn him when parliament is full of people who are way worse than him, who have avoided taxes, stolen public money and worked against the people. This country would be nothing without him."

Berlusconi repeated his familiar complaints against Italy's judiciary, blaming reckless magistrates for his legal problems.

"It is a bitter day, a day of mourning for democracy," Berlusconi told the crowd, adding that other leaders, including Beppe Grillo, the former comedian and head of the anti-government Five Star Movement, were powerful figures in politics despite not holding office.

"We are here, will be here and will stay here," he vowed.

Berlusconi, a billionaire media mogul, forced a confidence vote against the coalition government last month, hoping to force new elections.

But key allies rebelled, forcing Berlusconi to perform a U-turn and support the government.

His enemies have long blamed him for debasing Italy's political culture and have accused him of using politics as a tool to advance his business interests and increase his fortune.

Berlusconi's legal woes

Here are some of the legal cases involving Silvio Berlusconi

* THE MEDIASET CASE - In August Italy's Supreme Court confirmed a conviction and jail sentence against Berlusconi for tax fraud, his first definitive conviction.

* THE RUBY CASE - Berlusconi is appealing a June conviction for abuse of office and paying Moroccan nightclub dancer Karima El Mahroug for sex in 2010, when she was 17, below the legal age for prostitution.

* THE WIRETAP CASE - In March a Milan court sentenced Berlusconi to a year in jail after his family's newspaper published a transcript of a leaked wiretap connected to a banking scandal.

* THE MONDADORI CASE - The Supreme Court in September ordered Berlusconi's family holding company to pay €494 million (HK$5.2 billion) in damages over the disputed purchase of publisher Mondadori.

* THE TARANTINI CASE - Prosecutors have accused Berlusconi of "inducement to give false testimony" over money he allegedly paid to businessman Gianpaolo Tarantini and others to buy their silence over his use of prostitutes.

* THE VOTE-BUYING CASE - Berlusconi has been accused of bribing a senator to change sides in parliament to help topple a former government.