Since its rapid rise in early 2009, scholars have advanced a variety of explanations for popular support for the Tea Party movement. Here we argue that various political, economic, and demographic trends and events – e.g., the election of the first nonwhite president, the rising minority population – have been perceived as threatening the relative standing of whites in the U.S., with the resulting racial resentment fueling popular support for the movement. This “decline of whiteness” explanation for white Americans’ Tea Party support differs from prior accounts in highlighting the role of symbolic group status rather than personal experience, or economic competition, with minority group members in generating perceptions of threat. We tested this explanation in five survey-based experiments. In Study 1 we sought to make salient the president’s African-American heritage by presenting participants with an artificially darkened picture of Barack Obama. White participants shown the darkened photo were more likely to report they supported the Tea Party relative to a control condition. Presenting participants with information that the white population share (Study 2) or income advantage (Study 3) is declining also led whites to report greater Tea Party support, effects that were partly explained by heightened levels of racial resentment. A fourth study replicated the effects of Study 2 in a sample of Tea Party supporters. Finally, Study 5 showed that threatened white respondents reported stronger support for the Tea Party when racialized aspects of its platform (e.g., opposition to immigration) were highlighted, than if libertarian ones (e.g., reduced government spending) were. These findings are consistent with a view of popular support for the Tea Party as resulting, in part, from threats to the status of whites in America.