Conventional wisdom holds that it is easy to predict behavior tomorrow but difficult to predict behavior next month or next year. Past research, however, found that implicit (but not explicit) attitudes may predict behavior before people have consciously decided. If so, then implicit measures may predict further into the future than explicit measures. We tested this hypothesis using panel data from a representative sample of Americans to predict votes for Mr. Obama versus Mr. McCain in the 2008 U.S. presidential election. Implicit and explicit attitudes were measured at different times up to two months before the election. As predicted, explicit attitudes became more predictive of voting as the election neared. But implicit attitudes were equally predictive of voting regardless of proximity to Election Day. This stability of implicit attitudes over time challenges commonly held views of attitude-behavior relations. Implicit measures may predict behavior further into the future than explicit measures.