We examine the major interest groups in the debate over allowing the re-importation of prescription drugs by utilizing a logit model and instrumental variables. Consistent with political support approach, the evidence suggests that Representatives are maximizing their electoral prospects: contributions from pharmaceutical manufacturers shrink the probability of voting for the bill; and Representatives are sensitive to their constituencies – employees of pharmaceutical manufacturing and senior citizens. Representatives' gender and ideology regarding free trade and subsidies are also determining factors. However, the decision was, by and large, a partisan one: party affiliation was the most important factor in passing the bill.