TOKYO: Japanese voters are electing a new governor of Tokyo after financial scandals forced the previous two incumbents to step down.

In all, 21 contenders are vying to lead the sprawling capital and a number of other cities in the prefecture. However, analysts believe former Defence Minister Yuriko Koike, politician Hiroya Masuda and journalist Shuntaro Torigoe are the front-runners.

The winner will oversee preparations for the 2020 Olympics in Tokyo. Sunday's election was called after previous governor Yoichi Masuzoe resigned last month. He faced fierce criticism over allegations he used official funds to pay for holidays, art and comic books for his children.

Masuzoe, who won election promising a scandal-free administration, denied breaking the law, but admitted to ethical lapses around his lavish spending.

His predecessor, Naoki Inose also quit over a funding scandal in 2013, soon after Tokyo won the right to host the Olympics. Since then Tokyo's preparations for the 2020 Summer Olympics have been hit by scandals, overspending, administrative fumbles and construction delays.

One of the new governor's first duties will be to travel to Rio at the end of the 2016 Olympics in August to accept the Olympic flag as the next host.