I found these numbers interesting, and thought you might also. They are from the new Quinnipiac University Poll done between January 12th and 16th of a random national sample of 1,212 voters, with a 3.4 point margin of error.
There's still a couple of years before voters need to seriously consider who they want for president in 2020. That's a lot of time, and lots could happen to she things up between now and 2020.
But if we had to decide right now, Joe Biden is in a very good position. The public views him favorably by a 24 point margin. He is followed by Bernie Sanders with a 10 point margin and Oprah Winfrey with a 14 point margin. Kirsten Gillibrand is not known by enough of the public to have a good rating. And Donald Trump, who will probably be the GOP nominee, is upside-down with a 20 point negative margin.
Biden is also the only candidate to have more saying they would be inclined to vote for him than not. All of the other candidates are in negative territory on that question -- including Sanders and Winfrey. And Biden also leads all the other when you consider just Democrats and Independents (which would give him the inside track to get the Democratic nomination).
Voters might have a different attitude by 2020, but at least for right now, Joe Biden is the person to beat.
NOTE -- Other possible Democratic candidates (Cory Booker, Elizabeth Warren, Kamala Harris, etc.) were not included in this poll. I wish they had been, because it would be interesting to see how they rate with the public.