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Sen. Bernie Sanders (I-VT) speaks at a health care rally at the 2017 Convention of the California Nurses Association / National Nurses Organizing Committee in San Francisco.
UnitedHealth Group CEO David Wichmann warned investors on Tuesday that the "Medicare for All" proposals Democratic legislators and presidential candidates "will defend the country's health system."
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Despite concerns from UnitedHealth, growing the public support for a single payer system. According to a survey from Kaiser Family Foundation last month, 56% of survey people supported a national health plan where all Americans could get insurance from a single government plan, compared with 39% saying they violate it.