(CNN) If you saw any coverage of the first cattle call of the 2020 race this weekend at the California Democratic Party's annual convention, you almost certainly saw Bernie Sanders being treated like a conquering hero -- and anyone who voiced even a hint of moderation being booed.

Take former Colorado Gov. John Hickenlooper, who voiced the not-super-radical sentiment that "if we want to beat Donald Trump and achieve big progressive goals, socialism is not the answer."

"Before he could get finish his next sentence, a chorus of boos along with a sea of waving 'Bernie' signs overtook his speech, lasting for more than 30 seconds. The moment prompted Hickenlooper to attempt a smile and eventually break from his remarks to add, 'You know, if we're not careful, we're going to end up helping to re-elect the worst president in history.'"

Former Maryland Rep. John Delaney got similar treatment from California Democrats when he said that "Medicare for All may sound good, but it's actually not good policy, nor is it good politics."

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