However, he is also offering old Liberal Democratic Party (LDP)-style pork barrel benefits with promises to spend funds on public works, which directly challenges the DPJ manifesto’s ‘from concrete to people’ mantra.

Prime Minister Kan is being much more cautious about spending. Kan is also offering more to clamp down on money politics (Ozawa’s weak point) with a proposal for banning companies and groups from making political donations. Ozawa is only calling for political funding to be made public. Kan wants the allocation of funds within the DPJ to be transparent, in other words, to stop a secretary-general like Ozawa from single-handedly wielding money power in the party.

In the campaign, Kan has criticised Ozawa, saying that his ‘way of politics is based on financial strength and the large numbers in his group. It is deeply coloured by the principle of money and numbers (kane to kazu), and I’m not the only one who thinks so, am I?’. Kan has vowed to replace old politics with ‘clean and open politics,’ which is more open. This sums up the Kan model of politics. It echoes that of key members of Kan’s government and party executive consisting of the non-Ozawa club of ‘seven magistrates.’ This group has tried to cultivate a new DPJ culture which is the antithesis to the culture represented by Ozawa.

In many respects, Ozawa has been a visionary in his endeavour to change key institutional aspects of the Japanese political system. The problem with Ozawa is that he remains stuck in an old paradigm. He has never been able to leave ‘old’ politics behind. He has continued to operate outside the new rules he was instrumental in setting as if they did not apply to him. For example, Ozawa argues for the consolidation of power in formal positions of government along constitutional lines, yet he himself continues to rely excessively on an informal power base and its associated political networks, conventions and methods. He uses these to exert influence over government policy as well as party politics.

The old style of politics that Ozawa practises is quintessentially LDP-style politics. He has brought LDP policies and practices into the DPJ, which ultimately disqualifies him as a reformer. Ozawa’s political style is modelled on that of his former mentor and faction leader Tanaka Kakuei. This style has prevailed in Japan from the 1970s until Koizumi arrived in office in 2001 and tried to root it out by ‘destroying the LDP’ and offering a different type of leadership based largely on direct policy appeals to unaffiliated urban voters.

Ozawa has effectively prevented the DPJ from building a new organisational identity and thus hindered the crucial role that the DPJ needs to play if a two-party system is to be consolidated in Japan. In 2009 the DPJ won by rejecting LDP-style politics. The DPJ differentiated itself ideologically from the LDP in terms of a simple centre-left versus centre-right divide, but it also wanted to stand for a new type of politics. Ozawa has effectively blocked this.

This may mean Ozawa’s role might ultimately prove destructive, not creative, for the party of regime change in Japan. To the DPJ, Ozawa has been both a curse and a blessing – he built it into a majority party with his electoral genius and yet he has brought it down with his scandals. He has undeniably made a big contribution to enhancing the DPJ’s fortunes, but he seems now to be engaged in a struggle for his political survival by resorting to all his tried-and-true political and policy reflexes. An Ozawa victory next week will present him with an entirely new challenge and a novel political situation for Japan. A victory will see Ozawa lead from the front (after a long time as party secretary-general) and a restoration of the status quo ante for the DPJ. A Kan victory, on the other hand, will continue the current status quo in which the seven magistrates remain in ascendancy. It will also give the best chance for the DPJ to divest itself of the last vestiges of the Tanaka model.

Whatever happens on September 14, Ozawa will at some point ‘disappear’ from the political scene permanently rather than just at regular intervals, which has been his practice. Whether this will mean that ‘new’ politics will flourish remains an open question. One thing we can be sure of, however, is that Ozawa’s departure from the political scene will become a turning point in the history of Japanese politics.

Aurelia George Mulgan is Professor of Politics at the Australian Defence Force Academy of the University of New South Wales.

This piece excerpts sections of the Japan Forum Toshiba Prize lecture delivered to the British Association of Japanese Studies Conference in London, 9-10 September 2010.