Preliminary results indicate that reformist candidate, Mr Junichiro Koizumi, has unexpectedly emerged as the front runner in the race within the Liberal Democratic Party (LPD) to replace lame-duck Japanese Prime Minister, Mr Yoshio Mori.
However, with two days to go before the main elections, in what has been a surprisingly open contest, few are ruling out the possibility of a victory by former leader, Mr Ryutaro Hashimoto.
Votes by rank-and-file and local officials of the ruling LDP around the country are still being counted, but Mr Koizumi is predicted to emerge victorious after winning 17 out of 47 local party chapters by last night.
The result increases his chances of winning the LDP presidency tomorrow. As the LDP dominates a three-way coalition government, the victor will almost certainly become the country's next prime minister.
However, the winner needs to secure a majority of votes from both local chapters and 346 LDP members of parliament in tomorrow's election. Mr Hashimoto, a party stalwart has the support of the largest LDP faction, and is expected to be a tough competitor.
The two other candidates, LDP policy chief, Mr Shizuka Kamei, and Economics Minister, Mr Taro Aso, are now expected to have little chance of victory, although they may hold the balance of power if no clear winner emerges tomorrow.
Many political commentators here have judged the election Japan's most open leadership contest in years. Traditionally, the LDP has considered itself immune from popular opinion on this issue, with the victor simply chosen by the largest faction within the party.
The grassroots show of support for Mr Koizumi is widely interpreted here as a protest vote against a party leadership that has suffered from a series of political scandals and performed dismally in the face of mounting economic problems.
