Blind adoption of opinions put forward by political parties and influential figures can sometimes be harmful. Focusing on cases where the partisan gap on policy support has not yet arisen, we investigate whether its formation can be prevented by encouraging prior active engagement with non-partisan information. To address this question, we recruited N=851 Republicans for a study about net neutrality, an issue largely unfamiliar to the electorate, which refers to equal treatment of all internet traffic. In a pre-registered experiment, we randomly changed the order in which the following two types of information were provided: (i) partisan, underscoring Republicans’ opposition and Democrats’ support, and (ii) non-partisan, where the participants evaluated factual arguments about the pros and cons of the policy. Despite holding total information constant, we find that those who saw the non-partisan block first donated 46% more to a charity advocating for net neutrality (p=0.001). The treatment effect persisted in an obfuscated follow-up study, conducted several weeks after the intervention. However, we do not find an effect on donations when repeating the main study with a sample of Democrats.