Senators Chris Murphy (CT) and Jeff Merkley (OR) introduced a new Democratic health care proposal that would allow all individuals, regardless of age, with private or public insurance to buy into Medicare. The lawmakers described their proposal as “the public option on steroids.” The proposal, called the Choose Medicare Act, would offer Medicare coverage as an option for all individuals and for private businesses to offer their employees. The legislation would create a “Medicare Part E,” because new benefits such...