ROME -- In a bid to quiet growing political chaos, Italian lawmakers on Saturday elected President Giorgio Napolitano for a second term, turning to the 87-year-old statesman as the last best hope to break a profound deadlock in the euro zone's third-largest economy.
The move raised the possibility that Mr. Napolitano could preside over the creation of a broad-based coalition after inconclusive national elections in February split Parliament into three intractable factions and failed to yield a government even as Italy's economy continues to stumble.
The election of Mr. Napolitano, supported by both the main center-left and center-right parties, suggested that the two sides might be more willing to negotiate the formation of a government. But it also infuriated the anti-establishment Five Star Movement of Beppe Grillo that won a quarter of the recent parliamentary vote.
Mr. Grillo called his supporters to the streets on Saturday to protest, saying the re-election did not represent the change that Italians had seemed to demand. While he cannot prevent a grand coalition from forming, Mr. Grillo could complicate the situation by stirring renewed anger against the old political establishment, which is in upheaval.
Mr. Napolitano's existing seven-year term is up in May. Lawmakers on Saturday implored Mr. Napolitano to stand for president after failing to cohere around a candidate acceptable to a majority of Parliament in two days of voting, and after the implosion on Friday of the center-left Democratic Party.
"I cannot dismiss my responsibility toward the nation," Mr. Napolitano said before the vote, which made him the first second-term president in Italy's 67-year-old republic. But he added that he expected the political parties that had called on him would show "a corresponding sense of responsibility."
"We must look at the difficult situation of the country, the problems of Italy and Italians and the image and the institutional role of this country in the world," he said in a televised statement after the vote and a meeting with the presidents of the Lower House and the Senate.
Although a testament to the respect he commands among all parties, Mr. Napolitano's candidacy was a controversial solution that underscored the profound difficulties Italy's established parties face in adapting to new economic and social realities.
His candidacy was "not a sign of health of the Italian political system, even if the effect could be positive," said Antonio Polito, a political commentator. "Our system is no longer able to produce a stable government. The parliamentary system is broken, and it has not been able to fix itself."
Mr. Napolitano said in his statement that a possible government had not been discussed, but political analysts saw the likelihood of a grand coalition. Such a government would most likely exist as long as it takes to push through urgent economic measures and some critical reforms, including a new electoral law.
If the currently antagonistic parties do not come together, Mr. Napolitano could also dissolve Parliament and call new elections, though analysts said that was less likely because new elections would probably produce a similar result unless the electoral law was changed.
In November 2011, Mr. Napolitano helped orchestrate the rise to power of the current caretaker prime minister, Mario Monti, after former Prime Minister Silvio Berlusconi stepped down during a period of intense market turmoil. Mr. Monti's yearlong technocratic government ended in December when Mr. Berlusconi's party withdrew support, and national elections were held in February.
The Democratic Party won a majority in the Lower House but not in the Senate, and its leader, Pier Luigi Bersani, had rejected Mr. Berlusconi's proposal for a grand coalition.
But in a dramatic defeat, Mr. Bersani stepped down late Friday evening after rebels broke ranks and voted against the two presidential candidates proposed by the Democratic Party leadership. His resignation may lead to new leadership that might be more open to sharing power with Mr. Berlusconi's party, a prospect that has split the left.
Some analysts believe that the issue of immunity for Mr. Berlusconi, who is facing trials on accusations of corruption and paying for sex with a minor, was also a factor that led to the split within the left over the choice of a presidential candidate. A president has the power to make Mr. Berlusconi a senator for life, allowing him to keep parliamentary immunity.
The Democratic Party backed as its first choice a former labor union leader who had the support of Mr. Berlusconi, a decision that prompted significant disapproval among its electorate because it was perceived as a step toward an accord with the center-right.
The Five Star Movement refused to ally with the Democratic Party or to back its candidates for president. The movement backed the jurist Stefano Rodotà for president, a former leader of the center-left, which nonetheless did not back him.
Polls show that if parliamentary elections were held tomorrow, Mr. Berlusconi's coalition would receive the most votes, although Parliament would remain split into three blocs.
Writing on his popular blog, Mr. Grillo called the renomination of Mr. Napolitano "a coup d'état" and said he would march on Parliament on Saturday evening. Although his followers gathered in central Rome, Mr. Grillo, who was out of town, later said he would meet them Sunday.
Policy experts said that even with the profound political crisis, Italy had largely escaped greater market turmoil because of the decision by the European Central Bank last summer to create a mechanism to pump liquidity into the market and stabilize the euro.
Still, the political turmoil is preventing leaders from taking steps to right the economy, which is struggling to emerge from the longest recession since World War II. Unemployment is above 11 percent, and the national debt has risen to 130 percent of gross domestic product, the second-highest ratio of debt in the euro zone after Greece.
Since January, 4,468 Italian companies have gone out of business and 79 have defaulted, the commentator Guido Gentili wrote on Saturday in the economic daily Il Sole 24 Ore.
"The way the political system has behaved over the last few weeks showed that the idea the country is on a bad equilibrium hasn't really sunk in," said Federico Fubini, an economics commentator at the country's leading daily newspaper. "They say they understand, but they don't really understand."
"Now we are moving into uncharted waters, we can make it a success with new leadership on the left and the right and a new political system, or we can botch it," Mr. Fubini said.
Elisabetta Povoledo reported from Rome, and Rachel Donadio from Athens.
This article originally appeared in The New York Times.