Former Environment Minister Shinjiro Koizumi has support from the biggest number of Liberal Democratic Party lawmakers in the race to pick the successor to the party's president, Fumio Kishida, a Jiji Press survey found.

Ahead of Friday's voting, Koizumi, 43, was backed by over 50 LDP lawmakers, according to the survey of LDP lawmakers and others conducted by Sunday. Meanwhile, key rival candidates Sanae Takaichi, 63, economic security minister, and Shigeru Ishiba, 67, former LDP secretary-general, each had around 30 supporters.

Based on interviews with officials in the camps of all nine candidates and executives of LDP local organizations, Jiji Press also found that Takaichi, Koizumi and Ishiba are likely to win many votes from rank-and-file party members and party supporters.