Washington (CNN) Here's a number to chew on: 71%.

That's the percentage of Democrats in new Gallup polling that say their health care is either "excellent" or "good." Which is a very interesting finding given that the biggest divide within the 2020 Democratic field is over health care.

On one side are former Vice President Joe Biden and South Bend Mayor Pete Buttigieg, who support a sort-of mend-it-don't-end-it approach to the current law of the land -- the Affordable Care Act. Both Biden and Buttigieg support keeping the Affordable Care Act, passed into law by President Barack Obama, while seeking to fix the parts of the law -- high premium costs, lack of choice -- that have come under criticism.

On the other side are Sens. Bernie Sanders (Vermont) and Elizabeth Warren (Massachusetts), both of whom support "Medicare for All," which would get rid of all private health insurance in favor of a government-run system. Their argument is that the current system -- put in place by Obama -- is an improvement on what it replaced but is simply not enough, and needs to go in order to be replaced by a public health insurance system.

If you are Sanders or Warren, the Gallup numbers have to give you some pause. When seven in 10 of your voters say they are happy with something -- anything! -- it is usually inadvisable to stake your campaign on the idea that the thing they like needs to be fundamentally altered.

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