An outsider might suspect that Toshio Komoto is campaigning against the Liberal Democratic Party instead of running for its highest position.

A speech here yesterday in his home district -- ostensibly made as part of his campaign for this Sunday's parliamentary elections -- became a kind of litany of complaints against his party. He declared that it is so torn by factions that unity is impossible. The party's decisions represent factional preferences, not what is best for Japan, he said.

Leaders, he said, cannot take the haigh ground of moral principle to do what is right and to lead. He called for an end to factions and said that a new generation of younger leadership is necessary if the party is to lead Japan in the coming decade.

Such complaints would have been routine election rhetoric coming from a Socialist whipping the ruling party in parliament, but Komoto has his eye on the presidency of the Liberal Democrats -- and ultimately on the prime ministership of Japan.

The enthusiastic response his remarks received in the crowded Tatsuno City Hall auditorium, showed that whipping the Liberal Democratic Party is popular stuff no matter who does it.

In an election devoid of other issues, the ruling party is becoming the only issue. Even stalwarts deplore the corruption scandals that marked it in the 1970s, and the continuous feuding of factional leaders is unpopular.

After Sunday's parliamentary election, the Liberal Democrats must choose a new party president to succeed prime minister Masayoshi Ohira, who died unexpectedly last week. If the party maintains its controls of the lower house of the national legislature, the president will almost certainly become premier.

Komoto, a businessman turned politicaian, has sensed the mood for change and pegged his campaign to lead the government to the demand for reform and new blood. His leading rival within the party is Yasuhiro Nakasone, a factional leader.

In the past three weeks, a significant campaign has gotten under way among some younger party members to keep out the elders who dominated politics in the past decade and put Young Turks untainted by past scandals in high party positions. The public seems to be in a housecleaning mood, too, out of irritation with the long chain of scandals among members of the ruling party and in the bureaucracy.

Although 68 years old, Komoto seems to be the one best able to capitalize on the movement. He comes from a party faction that induced modest reforms in the mid-1970s. A wealthy man in his own right, he has never been seriously tainted by charges of corruption.

Komoto also has strength in the Japanese business community, which exerts great influence in the party's elections. He is regarded as a practical businessman who understands economics both in theory and practice.

Komoto was a boy wonder of the business world in the 1930s, when as a college student he founded a steamship company and then transformed it into the engine of his great wealth.

He has been elected 11 times to the lower house and twice has been head of the influential Ministry of International Trade and Industry, which makes many of Japan's key economic decisions. Outwardly a dry, unemotional man, the press has dubbed him the "unsmilling prince" for his dour public demeanor.

Some observers are skeptical of his party-reform platform. Pointing out that other politicians have spoken of similar changes and failed to follow through. The party factions were supposed to have been dissolved two years ago, but they have remained as strong as ever, promoting the wheeling-and-dealing tactics that mark every prime ministerial election.

Komoto has not spelled out exactly how he hopes to get such powerful factional leaders as former prime ministers Takeo Fukuda and Kaukuei Tanaka to dissolve their cliques in the lower house. The factions are tightly bound by ties of money, friendship and personal loyalties, each one competing for the benefits derived from the election of its leader as prime minister.

When pressed in a recent magazine interview, Komoto explained his reform plan simply by saying that all leaders should declare their factions dissolved. New leadership then would spring up naturally, he said.

In the speech to supporters here yesterday, Komoto said he is deeply worried about Japan's future under the current leadership. "The reason is very simple," he said. "Actions and judgments are based on fractional thinking. We must change the Liberal Democratic Party into a mature, well-organized modern party."

He said he had discussed the issue with Ohira in May and quoted him as promising to strive for the abolition of factions after the election.

Komoto grew up in this small west-central city near the Inland Sea and has a large following among his conservative constituents. Hundreds turned out yesterday for a kind of home-coming campaign event. Businessmen and political supporters praised him as the local boy who made good and who would, at last, give the region its first prime minister.

A local legislator, Noboru Ogawa, observing in a speech that Komoto had been minister of international trade and insustry and head of a Liberal Democrat policy council, said, "Now heaven has ordered that he become prime minister of Japan."