In this article we examine the mechanism by which the political opinions of Turkish citizens can be explained on the basis of attachments to Islam and the Turkish nation. Using insights from political psychology we review the dynamic role of these considerations as determinants of political judgements. We explore studies that question the appropriateness of a unidimensional scale of Islamism vs. Secularism in explaining citizens’ political placements, and we argue that the two ideologies can influence concurrently the way citizens think about politics. We use data from our survey of 107 Turkish citizens conducted in 2009 to examine whether attachments to Islam and the nation function as co-determinants of public attitudes. We focus on the political orientations of supporters of the Republican People’s Party (Cumhuriyet Halk Partisi, CHP). We expect that Kemalist nationalism but not Islamist attachments dominate the considerations ofthese voters in line with their party’s positions. We uncover significant evidence of Islamist considerations in their evaluation of political issues indicating that Islamist and nationalistic considerations co-shape citizens’ attitudes.