The discourse on solar geoengineering (SG) is evolving, yet public perceptions of SG as a climate change solution remain underexplored, especially in the polarized US political landscape. We examine the relative importance of different SG narratives-framed as complementary, substitutive, or posing a moral hazard-and partisan information sources in shaping public attitudes. Using a conjoint experiment with 2123 American voters, we find that partisan alignment with the information source plays a decisive role in shaping trust in the messenger and support for SG, overshadowing any impact of message framing. Both Democrats and Republicans are more likely to trust the messenger and support SG when the information comes from a copartisan source. However, despite these strong partisan influences, policy preferences remain consistent with ideological baselines. These findings highlight the importance of partisanship in shaping perceptions of emerging climate technologies such as SG, even in contexts of low public awareness, and underscore the challenges of depolarizing public discourse on climate change solutions.