Opposition to Single-Payer Health Care
According to the Washington Post, it comes from Jonathan Gruber.
Instead, Gruber argued for a more incremental approach, like the one in Massachusetts he helped write. Its central elements would be providing subsidies to people who are unable to pay for health care, increasing the number of those who are enrolled in public programs such as Medicaid and creating a public agency to help anyone ineligible for the programs buy health insurance.
The article confirms what I wrote recently, which is that Democratic politicians would be too risk-averse to tamper with existing employer-provided health insurance.