BUDAPEST -- Karoly Grosz started his work as Hungary's prime minister in June with a bluntly worded promise to shake up the economy. Then he skipped his summer vacation to hold marathon meetings with experts, pledged loyalty to Moscow with an official visit and returned to flatter Hungarian dissidents in a wide-open press conference.

If this high-profile, high-energy approach evokes the style of Soviet leader Mikhail Gorbachev, the resemblance is surely intentional. Since his installation as the day-to-day manager of Hungary's government, Grosz, 57, seems determined to succeed veteran communist party leader Janos Kadar and inaugurate Gorbachev's generation of leadership in Eastern Europe.

"He has had a very dynamic start," said Ivan Berend, the president of the Hungarian Academy of Science. "Grosz has made it clear that he wants to act, he wants to achieve results. And also that he's a very ambitious man."

The prime minister's drive may be crucial for Hungary, which over the past several years has suffered from an economic downturn and increasing public frustration with the 75-year-old Kadar's seemingly exhausted leadership. Acknowledging these problems, Grosz said earlier this month that his key task was to restore confidence in the government even as he introduced economic austerity measures and new reforms of socialism.

At the same time, Grosz's political profile is interesting for what it suggests about the future of communist leadership in the East Bloc under Gorbachev. For now, all but one of Moscow's six East European allies -- the exception is Poland -- are led by aged veteran communists who are generally resistant to Gorbachev's ideas and style but also presumably near the end of their careers.

Hungary, in Grosz and his chief rival, party propaganda chief Janos Berecz, is providing some of the first clues about what the successors to these men may be like. Although Gorbachev has nominally renounced heavy-handed Kremlin interference in East European politics, Budapest's contenders are emerging as firm Soviet loyalists and relative political conservatives who have quickly adopted the new Moscow leader's rhetoric and style.

Grosz, ironically, had a reputation as an ideological hard-liner before beginning his rapid shift toward the ideas and technique of Gorbachev's policy of glasnost, or openness.

"He's changing his image at such an abrupt rate that it's amazing," said Miklos Haraszti, a prominent Hungarian dissident writer. "He makes no promises about political reform, but he talks constantly about change in style. By that he means a change from Kadar's style to his version of Gorbachev."

Some aspects of the political process already seem to have changed. While secrecy has dominated choices of past party leaders in Eastern Europe and candidates have been difficult to identify beforehand, Budapest's new contenders are more or less openly competing for public and party favor.

Both Grosz and Berecz have assumed a high profile in the past year with interviews, speeches and television appearances. Grosz in particular has worked to counter negative feelings about him in intellectual circles. As prime minister, he has deftly diverted some of the limelight from Kadar and threatens to make his boss appear a distanced, king-like figure who watches passively while the government runs the country.

Yet if Kadar's 31-year reign is nearing an end -- and the party leader says he plans to stay on for several years -- Grosz still has a hard road to the top. To win the post, he will have to show communist activists that he can lead Hungary out of its economic crisis and make its reformed version of socialism work without undermining the party's power.

To achieve that task, in turn, Grosz's government will have to be relentless in administering a temporary decline in living standards almost certain to make the government unpopular. "It's not likely that this government will go down in history as one of the most triumphant ones," he conceded dryly two weeks ago in a press conference for western and Hungarian journalists. "More likely it will cause lack of sympathy and tensions."

Some Hungarian observers believe that Grosz may have been picked by Kadar as an ideal candidate for administering the bitter medicine. Throughout his career, they say, Grosz has proven both tough and savvy in carrying out his tasks, adeptly shifting with political winds but determined to show practical results.

Born in industrial Miskolc, Hungary's second-largest city, and trained as a printer, Grosz first achieved prominence as party secretary for Hungarian radio and television in the 1960s before moving to the party's propaganda apparatus in the 1970s. It was as head of the Agitprop department in the mid-1970s that he earned much of his repute as a dogmatist, siding with party forces that stalled and pushed back Hungary's early economic reform program of 1968.

In 1979, as proreform forces began to gain the upper hand again, Grosz was sent back to Miskolc for several years. In 1984, however, he was named head of Budapest's party organization and in 1985 he won a seat on the ruling Politburo.

Characteristically, Grosz has moved aggressively since returning to Budapest to bolster his image among influential intellectuals while seeking to perpetuate his reputation as a moderate populist sympathetic to the concerns of average workers. In a recent meeting with one group of intellectuals, he was critical of his own role in the 1970s and stressed that he now fully supported reforms of socialism, a participant said.

In other meetings with westerners, Grosz has deliberately raised and denied charges that he holds anti-Semitic views. In part, these widely circulated allegations stem from a remark Grosz reportedly made at a closed Budapest party meeting in which he introduced himself by saying, "My name is Grosz but I am not a Jew."

During one talk with a western visitor, Grosz insisted that the remark had no anti-Semitic meaning and outlined work he said he had done to support Hungary's Jewish community, according to a participant.

In the past three months, Grosz has worked so hard to project an image of openness that irreverent Hungarian observers dubbed the campaign "Grosznost," in reference to Gorbachev's glasnost.

Some Hungarians suspect, however, that Grosz's openness does not go further than such public displays. Both in public and in private, he has been cool or even openly hostile to proposals for major political reforms. He has also made it clear that he will not take steps -- such as the cancellation of costly "joint investments" with the Soviet Union and other East Bloc countries -- that risk Moscow's ire.