A mix of fresh faces and old hands are being offered up as the leading Democrats to challenge President Trump in 2020 in a new national poll that finds all would win.

The latest Public Policy Polling survey suggests five potential Democratic primary candidates: former Vice President Joe Biden, California Sen. Kamala Harris, Massachusetts Sen. Elizabeth Warren, Vermont Sen. Bernie Sanders, the 2016 Democratic challenger, and New Jersey Sen. Cory Booker.

Biden holds the widest margin of support, said PPP. In a matchup, Biden would beat Trump 54 percent to 41 percent.

However, as with all the potential candidates, the support comes mostly from past backers of Hillary Clinton.

The PPP results:

Biden beats Trump, 54 percent to 41 percent.

Booker beats Trump, 43 percent to 41 percent.

Harris beats Trump, 42 percent to 41 percent.

Sanders beats Trump, 51 percent to 41 percent.

Warren beats Trump 46 percent to 43 percent.

Added the pollster, "By a 53/41 spread, voters wish Barack Obama was still President instead of Trump."

Paul Bedard, the Washington Examiner's "Washington Secrets" columnist, can be contacted at pbedard@washingtonexaminer.com