The Upper House election may have already faded from the minds of the public, but two weeks after the excitement of the nation going to the polls, Nagatacho is back to business as usual: deal-making and politics.

With pro-constitutional revision groups only four seats shy of the 164 seats needed to secure a two-thirds majority in the house and pave the way toward constitutional change, it could be the Democratic Party for the People with its 23 Upper House seats that tips the balance.

In recent weeks, a tug-of-war between the pro- and anti-revision forces has been playing out within the DPP, with DPP leader Yuichiro Tamaki wavering between the two sides and failing to take a clear stand either way.