Three months after taking office, Prime Minister Shinzo Abe still enjoys strong public support for his Cabinet while talking of bolder moves to kick-start the ailing economy. But a warning light is flashing on a key issue on his to-do list: election reforms.

The issue of vote-value disparities, or the gap in the value of each vote between the least- and most-populous constituencies, is dominating the political arena, with recent court rulings declaring the imbalances in violation of the Constitution's guarantee of voter equality.

Abe's governing coalition is trying to move swiftly to address the vote-weight gap after the judiciary blamed the legislature for taking its rulings "lightly." But the opposition camp is seeking swifter and more comprehensive reforms.