A variety of scenarios await the country should the ruling coalition lose its majority in the Upper House — from an enlarged coalition to an opposition-led government.

TOKYO -- Japanese were voting Sunday for seats in the smaller of Japan's two parliamentary houses in a key election with Prime Minister Shigeru Ishiba and his ruling coalition facing a possible defeat that could worsen the country's political instability.

Japan's upper house election on Sunday could shake up politics, with rising prices and a populist party gaining ground. What’s at stake for PM Ishiba and Japan’s future?