This chart reflects the results of the newest Economist / YouGov Poll -- done between March 10th and 12th of a national sample of 1,500 adults, with a 3.1 point margin of error.
It shows the percentage of Democrats (blue bar) and the general public (green bar) that hold a favorable view of the Democratic candidates. All of these candidates (except Biden and O'Rourke) has officially declared they are candidates. Biden and O'Rourke were included because it looks like they will soon declare their candidacy.
