As Vice President Kamala Harris was in the final stages of selecting her vice presidential running mate, the Harris campaign had access to a wealth of research, vetting materials, and polling data on the potential finalists. This information played a crucial role in guiding the vice president's decision-making process.
According to sources familiar with the situation, none of the three finalists – Pennsylvania Gov. Josh Shapiro, Minnesota Gov. Tim Walz, and Arizona Sen. Mark Kelly – were found to significantly impact the Harris-Trump national match-up in the polling data. The same trend was observed in key battleground states.