35. Are there provisions for any other form of indirect public funding?

Source: 
政治資金規正法, 1948 (2022改正)
Political Funds Control Act, 1948 (as amended by Act No.68 of 2022)

第三十二条の四　個人が政治活動に関する寄附をした場合において、当該寄附についてこの法律又は公職選挙法の規定による報告がされたときは、租税特別措置法で定めるところにより、当該個人に対する所得税の課税について特別の措置を講ずる。

Article 32-4 Where an individual makes a donation related to political activities and a report on such donation is made pursuant to the provisions of this Act or the Public Offices Election Act, special measures shall be taken with respect to the taxation of income tax on such individual as prescribed by the Special Taxation Measures Act.

Donors can deduct donations to parties or candidates from their taxes.