In the 2005 House of Representatives (HoR) general election, Komeito contested nine single member district (SMD) seats and won eight of them, gaining a total of 981,105 votes in the process. In the 2009 election, the numbers were eight, zero, and 782,984 votes. I’ll save you the arithmetic, but drop-off in votes gained proportionally approximates the drop-off in aggregate LDP votes in the regional proportional districts (RPD). This makes sense, since the LDP always throws its support behind the Komeito SMD candidates. Komeito suffered a much more modest decline in the RPDs, where it is supposed to have received some LDP help as well,, resulting in a 2005-2009 decline from 23 to 21. So how’s it going to do this time around?
The RPDs are likely to yield more or less the same proportion of votes in support of the LDP-Komeito coalition. But more parties will be contesting those votes, increasing the likelihood of wasted votes. Let’s give Komeito 21-22 RPD seats.
In the SMDs, the LDP is likely to be about as much absolute help as they were in 2009. However, the nine Komeito candidates only have to run faster than the guys behind them, and the DPJ candidates will be backsliding. In fact, two of those SMDs won’t have any DPJ candidates. Some of the Komeito candidates will also be running against incumbents who defected from the DPJ to the Ozawa camp. But none of them will have to run against candidates from Hashimoto-Ishihara’s ascendant Japan Restoration Party because of a preexisting arrangement between Hashimoto and Komeito through its Osaka chapter. This is particularly significant because six of Komeito’s nine SMD candidates are running in the Sokagakkai stronghold Kinki/Kansai area, where Hashimoto currently dominates, while two more are running in the Tokyo-Kanagawa metropolitan area, home court for Ishihara. 7-8 wins looks reasonable to me.
That’s a range of 28-30 seats for Komeito, a significant improvement from 2009 results and good news for the LDP-Komeito coalition in the first round ballot for a new prime minister after the HoR election. Mind you, this is a very rough estimate. But it should serve as a freeware outline on which you can project more detailed analyses.