Japan has elected its first openly gay male lawmaker to its legislature, known as the National Diet.

Taiga Ishikawa won a seat in the upper house, the House of Councillors, by running on a platform supporting marriage equality as part of the Constitutional Democratic Party.

Ishikawa told Reuters that his election shows hope for the future of same-sex marriage, which is currently not legal in the Asian nation and is opposed by Prime Minister Shinzo Abe.

“Since the early 2000s, the issue of same-sex marriage has progressed leaps and bounds,” the 45-year-old politician said. “It will happen within the six years of my term, I am sure.”

Ishikawa credited "the growing acceptance overseas of same-sex marriage" as influencing hearts and minds in Japan. Taiwan became the first Asian nation to welcome marriage equality in May. “I think we’ve got a breakthrough now and I plan to move the conversation forward," he added.

Ishikawa and Kanako Otsuji — Japan's first out lesbian lawmaker, who introduced a marriage bill in June — face considerable political opposition from the ruling Liberal Democratic Party. However, a recent poll from Dentsu found that over 78 percent of Japanese people (ages 20 to 60) support marriage equality.