This is just 1 data point, but Gallup reports:
Democrats' overall opinions of the major Democratic contenders for president have changed small despite six eventful weeks of campaigning. Hillary Clinton ruins the best liked amongst her party faithful. She enjoys a net favorable score of +60, which is essentially where she stood in July. Bernie Sanders is still the next best-liked candidate in the field, with his net favorable stable at +29.
Clinton is plus 4 net favorable with Dems in the last months. Something to keep an eye on.
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