Former vice president Joe Biden, Sen. Bernie Sanders (I-Vt.) and Sen. Elizabeth Warren (D-Mass.) run strongest against the president nationally, with Biden leading by 17 points (56 percent to 39 percent), Warren by 15 points (55 percent to 40 percent) and Sanders by 14 points (55 percent to 41 percent).
South Bend, Ind., Mayor Pete Buttigieg and Sen. Kamala D. Harris (D-Calif.), the other two Democrats tested against Trump, also lead the president among registered voters, with Buttigieg up by 52 percent to 41 percent, and Harris ahead by 51 percent to 42 percent.