Nishio's new party was received with great fanfare by the media in Japan and initially received support from a number of prominent centrist intellectuals, leading to talk of a "Democratic Socialist boom" in the spring of 1960. U.S. diplomats also placed great hopes on the new party as a much-needed more moderate alternative to the left-wing opposition parties in Japan. However, Nishio and his new party sat out the Anpo protests, even as they became much more heated and contentious in May and June, and in the fall 1960 general election Nishio refused to say whether the protests had been good or bad, which pleased no one in the polarized atmosphere of the time. Nishio was one of the speakers at the televised election debate that witnessed the spectacular assassination of Socialist Party Chairman Inejirō Asanuma, and his party's prospects may have been further damaged by a sympathy vote in favor of the JSP in the wake of Asanuma's killing. In the election just a few weeks later, the DSP suffered a disastrous result, falling from 40 seats in the Diet to just 17, while the JSP and LDP both increased their seat counts. Although the DSP managed to cling to a few seats in the Diet for a few more decades, it was never able to recapture the excitement it had accrued at the time of its formation, especially after the conservative LDP became more moderate under prime ministers Ikeda Hayato and Eisaku Satō.