Analyst Koichi Nakano of Sophia University, a private university in Tokyo, doubts the opposition can deliver on its pledges.

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Koichi Nakano, a political scientist, says the electoral arithmetic suggests this situation could last for another five years at least.

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Koichi Nakano of Sophia University in Tokyo points out that Japan's distorted electoral map exaggerates the size of the defeat: the DPJ lost heavily against LDP candidates in depopulated rural areas that are considered to be the opposition's heartland, but which produce a disproportionate number of seats.

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