At Saturday’s Democratic debate, Bernie Sanders was on fire about universal health care.

“We need a Medicare for all – single-pay system,” Sanders said. “It will lower the cost of health care for a middle class family by thousands of dollars a year.”

But he seemed a little flummoxed by the obvious question.

“Can you tell us, specifically, how much people will be expected to pay?” ABC’s Martha Raddatz asked.

He explained that, obviously, taxes would have to go up, however the payoff would be that you’d have no insurance premiums or deductibles to worry about. So the net effect?

“It will lower the cost of health care for a middle class family by thousands of dollars a year,” Sanders said.

“Senator, senator you didn’t really tell us, specifically, how much people will be expected to pay,” Raddatz pointed out.

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“They will not be paying, Martha, any private insurance, so it’s unfair to say in total…”

“But you can’t tell us a specific number,” Raddatz said.

“I can tell you that adding up the fact that you are not paying any private insurance, businesses are not paying any private insurance, the average middle class family will be saving thousands of dollars every year,” Sanders said.

I think the trouble with that promise is that it’s been tried before.

“Those cost savings are passed on to you, and we estimate we can cut the average family’s premium by about $2,500 per year,” President Obama explained in the past.

Now the Republicans are much more innovative. Their rebel candidate makes up promises that haven’t been tried before.

“I will build a great, great wall and I will have Mexico pay for that wall,” Donald Trump said.

Much more believable.