We present a boundedly rational model of party choice in mass elections, the aspiration adaptation (AA-) model of issue voting. This is based on aspiration adaptation theory (SELTEN and SAUERMANN, 1962; SELTEN 1998). A voter has a ‘party influence scheme’ describing her expectations about the directional influence that parties have on political issues. It determines which political realizations are expected to be feasible in the coming legislature period. The scheme is corrected using a simple learning rule after an incumbent party’s performance has been observed. Furthermore, a voter has ‘aspirations’ on political issues. A voters chooses the party that is expected to fulfil her aspirations. In case aspirations cannot be fulfilled, she adjusts them according to a ‘aspiration adaptation scheme’. The ‘party influence scheme’ and ‘aspiration adaptation scheme’ together are the basis for a boundedly rational but systematic procedure of party choice.