Sen. Bernie Sanders, I-Vt., promotes his Medicare-for-all proposal at the 2017 Convention of the California Nurses Association/National Nurses Organizing Committee in San Francisco, Calif., an issue that is dominating the early debate in the 2020 presidential contest.

Sen. Bernie Sanders, I-Vt., promotes his Medicare-for-all proposal at the 2017 Convention of the California Nurses Association/National Nurses Organizing Committee in San Francisco, Calif., an issue that is dominating the early debate in the 2020 presidential contest.