Democratic candidates for president in 2020 will likely include some type of public plan in their health care reform platforms. Existing public plans take many forms and often incorporate private elements, as do most proposals to extend such plans. We review the types of public plans in the current system. We describe and assess the range of proposals to extend these plans or elements of them to additional populations. We suggest questions that candidates could use to guide their decisions about the scope and content of their health policy proposals. Developmental work during campaigns will contribute to success in turning candidates' promises into accomplishments.