The Socialist who is likely to lead Italy's next government

Despite the hottest temperatures in more than a century, there is a whirl of excitement and a breath of change breezing through Rome's corridors of power. Bettino Craxi, the man designated to put together Italy's 44th coalition government since World War II, is well on the way to becoming Italy's first Socialist prime minister.

In a country whose leaders have come with rare exception from the Christian Democratic Party, this means more than a change of government or a new regime. Mr. Craxi represents a new face, a distinctive new style, fresh ideas, and a clear approach - ''a new frontier,'' as a political commentator put it.

Just as he shrewdly replaced the Soviet-style hammer and sickle with a red carnation as the symbol of his party several years ago, Craxi is now bent on projecting a new image of himself as Italy's leader and statesman.

In the month since the elections, Craxi's image has undergone a radical transformation. Formerly perceived as the opportunistic, overly ambitious leader of Italy's third largest party, scrambling to become prime minister at almost any cost, Craxi is now seen as a skillful, astute, Machiavellian power broker who is as sure of himself as he is of his rivals' limits and the country's socialist future.

More than ever before he is playing on the fact that neither the Christian Democrats, who lost 6 percent of their electoral support in June, nor the Communists, who don't have a majority, can form a government without his say-so.

Described as pugnacious, even rancorous at times, but generally broadminded, Craxi has been nicknamed ''the king'' because of his strong leadership abilities. A portrait describes the man as patient, soft-spoken, highly intelligent, strong willed, and unmistakably haughty.

He has also been dubbed the ''German,'' less for his attempts to model his party on the Social Democrats of West Germany than for the iron-fisted way he imposes his will. A poll last year among Italians revealed that only Pope John Paul II and Fiat chairman Giovanni Agnelli were considered more powerful.

Since the June elections, Craxi has become even more autocratic, his aides say. Where other parties often spend an entire day hashing out their strategies, Craxi's meetings with his party leaders are now reduced to lightning-quick 20 -minute sessions, with ''Bettino'' - as he is now familiarly called by staff and advisers - making a presentation and one or two others confirming the points they agree with.

More like an American-style politician than an Italian, Craxi has made his personality a part of his politics. More than any other Italian politician, Craxi plays to the people. A pre-election poll in June determined that the voters considered Craxi's personality to be his best asset. He has made the most of it, even though he has at times proved to be testy with the press.

Craxi is frequently seen dining in fashionable Roman restaurants. His close friendships with well-known writers, actresses, and musicians are no secret.

Few questions are asked about his private life, even though it is well known that he lives permanently in a suite in the chic, ivy-covered Hotel Raphael near the Piazza Navone, while his wife and two children live in Milan.

Aside from politics, his only known passion is collecting Garibaldi memorabilia. He is an avid fan of both the late John F. Kennedy and Salvador Allende, Chile's former president.

Craxi is a prolific writer and an enthusiast of art and the cinema, although his books are in the political sphere. For example, one book is called ''Socialism from Santiago to Prague.'' He strums the guitar adroitly and dresses casually - most often in jeans and a sport coat. Once, when he went to the Quirinale Palace, President Sandro Pertini told him to return when he was dressed ''more formally.''

Many of Craxi's political ideas, in fact, are no different from those of his predecessors, the Christian Democrats. Wooed by both the Communists and the Christian Democrats, Craxi finally decided midway through the last election campaign to throw in his lot with the Christian Democrats. Like them, he favors the installation of the cruise missiles in Sicily and bringing inflation down from 16 percent to 10 percent.

But the way he has so far gone about forming the new government is refreshingly different. Within days after Mr. Pertini asked him to form a government, Craxi had put together a highly trained staff of experts to draw up a specific plan of governing. This plan has been presented to the five prospective partners in the coalition for perusal and amendments.

This is the first time anyone can remember that such an exchange of detailed programs has been done and shown to the public during the formulation of a government. Of course, an analyst points out, ''Craxi is doing this as much to document the agreements as a kind of protective insurance, as he is to reach an accord on the specific plan of action.''

Craxi's climb has not been easy. A card-carrying Socialist since the age of 17, he assumed leadership of his party in 1976, when his predecessor, Francesco de Martino, was forced to resign after the Socialists made their poorest showing ever in an election.

The disappointing election results last June almost put Craxi in a similar bind. Although the Socialists did boost their share of the electoral pie from 9. 8 percent to 11.4 percent, that was considerably less than the 15 percent Craxi had been promising his Socialist colleagues.

But immediately after the elections, Craxi managed to convince his rivals both inside the Socialist Party headquarters and without, that the Socialists were the winners and he was their leader. His backing in the party suddenly shot up from 70 percent to 90 percent, insiders say.

On the outside, he was helped by the longer-term threat the Christian Democrats detect from former Prime Minister Giovanni Spadolini, whose Republican Party is smaller but was also a winner in the election. So significantly had Craxi's credit risen that it took Sandro Pertini less than 24 hours after consulting all the parties to ask Craxi to try to form a government.

But even without the detailed, written staff proposals, Craxi faces an almost impossible task of governing. Every decision, policy, and issue must first get the approval of each party in the coalition.

Whereas Spadolini saw himself as a mediator among the parties, Craxi sees his role as the prime minister of a Socialist government. At this point, it is unlikely that Craxi will be able to hold a coalition together any longer than Spadolini, since distrust and instability seem to be inherent in Italy's brand of democracy.