ROME -- Italian Prime Minister Enrico Letta on Thursday announced his resignation after surrendering to a leadership challenge from a party colleague who is widely expected to become Italy's youngest-ever prime minister.
The challenger, Matteo Renzi, 39, was overwhelmingly backed by the center-left Democratic Party after he demanded that a new government lead Italy out of a "quagmire." For 10 months, Letta has led a shaky coalition government that has struggled largely without success to push through key reforms.
Renzi, the popular mayor of Florence, who was recently appointed head of the Democrats, thanked Letta in a speech to party officials but pushed to take his place.
Letta said he would hand in his resignation Friday to President Giorgio Napolitano. Napolitano will then probably consult with political parties about a possible Renzi-led government. If Napolitano finds consensus, Renzi will be asked to form a Cabinet that will be put to a vote of confidence in Parliament, meaning it will be days before a new government takes office.
After two decades in which Italy's government has been evenly split between fans of former Prime Minister Silvio Berlusconi's brash anti-taxation politics and squabbling left-wing politicians united only by their fierce loathing of the conservative media mogul, polls show Renzi is the first center-left politician who appeals to Berlusconi voters. That suggests Renzi may find the consensus to reform a creaking bureaucracy and legal system, tasks that Letta and his predecessor, Mario Monti, tried to tackle with only mixed results.
Letta was named prime minister by Napolitano in April after inconclusive elections in February that saw the Democratic Party unable to gain control of Parliament because of a strong showing from comic Beppe Grillo and a resurgent Berlusconi, who had resigned as prime minister in November 2011.
Now, if Parliament gives the nod to Renzi, he will become Italy's third prime minister in three years to be appointed without a general election, a reflection of continuing political stalemate in a country stuck in recession.
Renzi has frequently said he would seek to take power only through a popular vote; polls showed 74% of Italians were opposed to another unelected leader. But on Thursday he indicated he was ready to take over the reins from Letta, even as critics condemned the move as a palace coup.
"Why did Renzi change his mind? This is the big surprise," said Roberto D'Alimonte, a professor of politics at Rome's Luiss University.
"Many have written to me saying, 'Watch out, you will burn yourself,'" Renzi said about his sudden decision. "But whoever enters politics is obliged to take risks sometimes."
Renzi said that if he had not taken chances in his career, "I would now be in my second term as head of the province of Florence."
On Thursday, the priest who served at the Florence church that Renzi attended as a child acknowledged the politician's fierce ambition, saying, "Even when he was a child, you could understand Matteo Renzi would be No. 1."
This year, the coalition Cabinet, which featured Berlusconi backers as well as Democratic Party members, became a frequent target for criticism from Renzi after he was elected party secretary in a December primary. The victory placed him in the uneasy role of running the prime minister's party.
Often compared to former British Prime Minister Tony Blair for his sound-bite appeal and charm, Renzi has called for a generational change in Italian politics, which has long been dominated by men older than 60, though Letta is 47. In a country tired of corrupt lawmakers, Renzi has also benefited from never serving in Parliament, although he also has been mocked by comedians for his perceived lack of substance.
Renzi, a keen admirer of President Obama and American author Dave Eggers, is a frequent Twitter user who plays U2 tracks at his congresses and recently posed in a leather jacket and white T-shirt in imitation of the Fonzie character from the old sit-com "Happy Days."