Ethnicity is a central theme in the analysis of Nigerian politics. Conventional approaches to ethnic politics in Nigeria often assume the existence of stable identities and consistent group motives. It is also commonly asserted that Nigerian political behavior is driven by ethnic solidarities. Ethnic political parties, clientelism, and social polarization are all associated with strong communal allegiances. These practices are regarded as inherently corrosive to a plural democracy. This paper questions prevailing assumptions about the salience and impact of ethnicity on Nigerian politics. Based on extensive survey data, I find that identity in Nigeria is fluid and contingent, with substantial variation among groups and over time. The relative construction of identity influences attitudes and collective action. When communal identities are construed politically, they have stronger effects on views and behavior. Moreover, institutions have a marked effect on the construction of identity and on political attitudes. In particular, the character of elections provides a key catalyst for the intensity of ethnic identification, the strength of political ethnicity, and attitudes toward democracy. Overall, the salience of ethnicity in Nigerian politics should be placed in perspective. There is no question that communal divisions are crucial in the political life of the country, but the “ethnic” and “civic” divide in Nigeria does not consistently shape attitudes toward democracy or modes of political participation. These findings suggest that democratic politics can play an important role in managing Nigeria’s plural society.