The 12-day campaign period began on Tuesday for the election in which 1,344 candidates compete for 465 seats in the House of Representatives.
The LDP and its coalition partner, Komeito, aim to maintain their majority, while the opposition Constitutional Democratic Party of Japan (CDPJ) hopes to capitalize on the ruling party's recent troubles.
CDPJ leader Yoshihiko Noda criticized Ishiba's decision to call an early election, calling it an attempt to divert attention from the financial improprieties.
"We are entering this election with deep remorse," Ishiba said in Fukushima Prefecture, addressing the scandal. "This is going to be an election to revive Japan. I will create a new Japan."
The election comes as Ishiba faces scrutiny over his perceived retreat from earlier policy goals, including the creation of a NATO-like alliance in Asia.
Rising living costs have also emerged as a key campaign issue, with both ruling and opposition parties proposing measures to support households.
Kyodo News reported that over 65 percent of respondents would consider the LDP's financial scandal when casting their votes.
However, the poll also suggested that the LDP remains the top choice for many voters, potentially benefiting from a fragmented opposition landscape.
