The Democratic Party of Japan swept to power last year promising to end a political system built on patronage and public works splurging that fed the world’s largest debt. Tomorrow, it will decide whether to replace Prime Minister Naoto Kan with a man who embodies both. "It’s just bad news all around," said Jeff Kingston, author of Contemporary Japan: History, Politics and Social Change Since the 1980s and a professor at Temple University, Japan Campus. "Kan hasn’t done much, but if the party elects the most unpopular politician in the country, it will lose all credibility with Japan's voters."