TOKYO - Three ruling party rivals formally launched campaigns on Friday to become Japan's next prime minister, registering to run in a race hawkish cabinet minister Shinzo Abe appears to have already wrapped up.

Japanese Chief Cabinet Secretary Shinzo Abe speaks to members of the ruling Liberal Democratic Party who support him as a candidate in the upcoming election to become the next Japanese prime minister, at the party headquarters in Tokyo September 8, 2006. [Reuters]

The 51-year-old Abe advocates a bolder role for Japan on the world stage and reviving traditional values at home. But some doubt he will be as forceful as combative Prime Minister Junichiro Koizumi in pushing economic reforms.

"I want to focus on what needs to be done to have Japan's economy grow steadily, and on reviving education," Abe told reporters before submitting his candidacy for the September 20 Liberal Democratic Party (LDP) presidential election.

"From the standpoint of emerging from the 'post-war regime', I want to show leadership on a new constitution," he said.

Abe, who would become Japan's first prime minister to be born after World War Two, has made revising Japan's pacifist constitution a linchpin of his platform.

The constitution was drafted by U.S. occupation authorities after Japan's 1945 defeat.

"I want to develop an assertive diplomacy," he added.

Two lagging challengers, Foreign Minister Taro Aso, 66, and Finance Minister Sadakazu Tanigaki, 61, also registered their candidacies, despite overwhelming odds against them.

The new LDP president is assured the premiership by virtue of the party's grip on parliament, which is expected to convene on September 26 to choose the new prime minister.

Koizumi is stepping down after more than five years in the top job, making him Japan's third-longest ruling prime minister since the end of World War Two.

BIG LEAD

Some 70 percent of LDP lawmakers have jumped on Abe's bandwagon and he is running well ahead among the party rank-and-file as well, media surveys say.

The well-dressed, softly spoken Abe - known for his tough stance on the emotive issue of Japanese abducted by North Korea decades ago - also has a big lead in surveys asking the broader public who they prefer as next prime minister.

The party is counting on the popularity of Abe, now chief cabinet secretary, to help them in an upper house election next summer.

Although the race looked over before it began, the LDP hopes to profit from the performance by keeping public interest alive.

"It would mean the end of the LDP if the curtain went up on September 8 and the people found out that the play was actually already over," Aso told reporters recently.

BEAUTIFUL CAMPAIGN

Abe, who is running under the slogan "Beautiful Country, Japan", has said one of his top priorities will be to revise Japan's education law to put patriotism in school curriculums.

He has also said he wants better ties with China and South Korea, chilled by Koizumi's annual visits to Tokyo's Yasukuni Shrine, seen by critics as a symbol of Japan's past militarism.

The Yomiuri newspaper reported on Friday that Abe was eyeing talks with Chinese President Hu Jintao on the sidelines of an Asia-Pacific leaders summit in Hanoi in November.

But Abe has been coy on two topics of keen public interest: whether he would visit Yasukuni if elected, and when and how much he thinks Japan's 5 percent sales tax should be raised.

Tanigaki says he won't visit Yasukuni and that Japan should raise the sales tax to 10 percent in by 2015 to rein in Japan's huge public debt.