This paper investigates whether the Japanese voters became happy and/or unhappy due to the results of the General Election in 2009. We conducted a daily web survey for seven days before and after the election, obtaining 1068 responses. Estimating a fixed effects model, we found that among those whose expectation differed from the reality, supporters of the Democratic Party of Japan (DPJ), the winner, became significantly happier, and supporters of the Liberal Democratic Party of Japan (LDP) and New Komeito, the losers, became significantly unhappier on the day following the election. However, happiness returned to the previous level in one or two days, implying people adapted to the news very quickly. On the other hand, the happiness level of those whose expectation of the election results were realized did not change. In a word, only unexpected results matter. Dividing those who support the policies of DPJ into two groups, those who expect material benefits from the victory of DPJ and those who do not, the obtained results suggested that the reason why the supporters of the winner (DPJ) felt happy was not because they obtained material benefits from the change of government.