Back in 1964, when the lay Buddhist organization Soka Gakkai founded Komeito, many people looked on warily: They believed it violated the Constitution's separation of religion and politics.

But in the week Komeito marked its 50th anniversary, observers say the party has successfully diluted its religious connotations and become a key player in politics.

"Komeito has changed its image," said Steven Reed, a political scientist at Chuo University. "Komeito in 1964, it was this one thing. Komeito in 2014 is another thing."