S/ Maeno Masanori, NTV Reporter / A record nine candidates have battled in the longest-ever election campaign period of 15 days, but the situation is still unpredictable, with contestants vying for votes until the last minute.

The election for president of the ruling Liberal Democratic Party involves 368 votes by Diet members and as many votes by rank-and-file party members for a total of 736.

Ishiba Shigeru, Takaichi Sanae and Koizumi Shinjiro are leading the polls, suggesting that the final outcome will likely be decided by a runoff between two candidates with the most votes.

Latest information indicates that Ishiba will have the upper hand in votes from rank-and-filers, while Koizumi will have the advantage in those from lawmakers.

But as LDP Vice President Aso Taro has expressed intention to support Takaichi, it has become unclear which of the three will advance to the final election.

The runoff will involve 368 votes by the LDP parliamentarians and 47 votes from each of the party's prefectural chapters for a total of 415.

Voting began at 1 p.m. on September 27, and the winner will be decided in the late afternoon.

The effective successor to outgoing Prime Minister Kishida Fumio and the party will be tasked with regaining public trust following a political fund scandal involving LDP factions and implementing policies.