The 270-seat threshold for victory that the LDP-Komeito coalition has set for itself and the 238-seat single-party simple majority for the LDP are more or less the same thing if you consider the following. Komeito has won 31 seats in three of the five general elections (34 and 21 in the other two) that it has experienced since it split from Ozawa’s forces and reverted to its role as the virtual political wing of the Sokagakkai, and will certainly perform similarly in this election.
Abe, though, is sticking to his own simple majority threshold for the coalition. Translation: I will not resign even if the LDP loses its single-party majority unless the coalition itself is voted out of office. The LDP will have to wait until the September leadership election. In the meantime, I am going to forge ahead with my legislative agenda. (Good luck.)
Finally, picking nits, also keep in mind that the LDP went into the election with 295 incumbents plus the nominally independent President of the House.