President Donald Trump trails at least three Democratic hopefuls -- Joe Biden, Bernie Sanders and Elizabeth Warren -- in theoretical head-to-head matchups for the 2020 general election, a new poll showed.

Biden, the former vice president, held the biggest lead among registered voters in the NBC News/Wall Street Journal poll released Sunday: 51% to 42%, well outside the surveys margin of error, which was plus or minus 3.5 percentage points.

Senator Sanders of Vermont led Trump by 50% to 43%, and Senator Warren of Massachusetts was up 48% to 43%. A fourth Democrat, Senator Kamala Harris of California, was up against Trump by a point, 45% to 44%.

Biden’s larger lead over Trump was largely due to his stronger performance among independent voters, white people and suburban residents than the rest of the Democratic field.

Trumps approval rating was at 45% against 52% who disapprove, broadly unchanged from the last few versions of the NBC/WSJ survey. He was at 89% approval among Republicans and had strong support from rural voters, men and older people.

The poll was taken July 7-9 of 800 registered voters, more than half of whom were reached by cell phone.