The standard model of strategic tax competition assumes that government policymakers are perfectly benevolent. We depart from this assumption by allowing policymakers to be influenced by the rent-seeking behavior of businesses. Campaign contributions may affect tax competition and enhance or retard the mobility of capital across jurisdictions. Based on a panel of 48 U.S. states and unique data on business campaign contributions, we find that contributions have a significant direct effect on tax policy, the economic value of a $1 business campaign contribution is nearly $4, the slope of the tax reaction function is negative, and the empirical results are sensitive to state effects.