Opposition to the Iraq War is thought to have contributed to the election of Barack Obama in 2008. The present study shows that controlling for other factors, including the percentage of the vote going to the prewar Democratic presidential candidate, states with relatively high levels of Iraq War military fatalities had a higher percentage vote for Obama. This result is consistent with a prediction derived from rational political theory and the results of several studies examining the impacts of war fatality rates in other military conflicts in previous elections. However, in the current study, we find that the effect of Iraq War fatalities on the percentage vote for Obama is conditioned by state military enlistment rates. Military fatalities have a strong effect in states with historically low military enlistment rates. But the effect disappears in states with very high levels of military enlistment.