Canada is often pointed to by some Americans as one of the examples they would like a U.S. system to emulate. "But it's important to understand that Canada has one of the most-narrow benefit packages in the industrialized world," says Kara Jones, a visiting fellow at Independent Women's Forum focusing on health policy.

She continues: "When you look at other industrialized nations that provide single payer or universal health care coverage to their citizens, Canada doesn't cover vision and dental care, it doesn't cover out-patient prescriptions, it doesn't cover long-term care or mental health – and these are all some things that Senator Sanders is looking to cover in Medicare of All."

In a related reportThe Associated Press says Medicare for All's rich benefits "leapfrog" other nations. "The real question is 'how are we going to pay for all of this?'" Jones argues.

Sanders offers various ideas on how to pay for Medicare for All. Most, if not all, of the proposals involve a premium or tax of some sort. Meanwhile, the plan would do away with private insurance. Both will be a hard pill to swallow for some consumers, according to Jones.

"180 million Americans get their health insurance through an employer, and this is good, comprehensive coverage that people have already," she notes. "What we need to be doing is looking at how to expand coverage to those who don't already have access to health care insurance."

Jones recalls that it was President Barack Obama who told Americans that if they liked their health plan they could keep their health plan.

"Well, this time around, that definitely would not be the case," she explains, "because those 180 million Americans who have access to private employer coverage … would be dumped into this new Medicare for All plan, this single-payer health insurance plan."