Biden remains the favorite for 2020 among Democrats and those leaning Democrat with 34%, says the poll conducted by Quinnipiac University. Massachusetts Senator Elizabeth Warren came in second with 15%, followed by California Senator Kamala Harris with 12%, and Vermont Senator Bernie Sanders with 11%.

By contrast, 54% of voters polled said they “definitely” will not vote for Trump, matching the “never Trump” percentage from a similar Quinnipiac poll conducted in May. Those polled also disapprove of the job Trump is doing as president (54% to 40%), compared to similar disapproval (53% to 42%) ratings from a poll conducted in June. 

However, 32% of those polled say they would “definitely” vote for Trump if he’s the Republican nominee in the 2020 presidential race, while 12% say they will consider voting for Trump.

The new figures come as the second round of Democratic presidential debates begins Tuesday in Detroit. The latest Quinnipiac poll of 1,306 voters conducted from July 25 – 28 is also a vast difference compared to a Quinnipiac poll earlier this month showing a closer race between Biden with 22%, Harris with 20%, Warren with 14%, and Sanders with 13%. 

That poll was taken shortly after the first Democratic presidential debate, when Harris stunned Biden, going after his recent remarks about working with a pair of segregationists when he was in the Senate, as well as his opposition to busing in the 1970s. Biden would later say Harris’ actions caught him off guard and her comments were “a mischaracterization of my position across the board, I did not praise racists.”

As Harris’ strong showing during the first debate gave her a brief boost poll-wise, closing in on Biden, she has since fallen in the latest Quinnipiac poll.

“In the blink of an eye, the post-debate surge for Sen. Kamala Harris fades, and former Vice President Joseph Biden regains his footing among Democratic presidential contenders,” said Mary Snow, a Quinnipiac polling analyst. 

Biden and Harris will face off again during the second night of the debates on Wednesday.

Meanwhile, Warren may be the wildcard among Democrats.

“Warren is holding steady in the support she’s seeing from Democrats and Democratic leaners and she remains the candidate seen has having the best policy ideas,” Quinnipiac’s Snow said. 

Still, Biden appears to have the best chance of beating Trump in the general election, 51% of Democrats polled by Quinnipiac, with 10% for Sanders and 8% each for Harris and Warren.

“Electability remains his strongest pull. Across the board, Biden remains by far the Democrat seen as having the best chance of defeating President Trump,” Snow concludes.

Biden is also currently winning most of the key demographics among Democrats, according to the latest poll: 53% of black Democrats and 34% of women Democrats.

After Biden, Warren, Harris, and Sanders, Peter Buttigieg was the favored overall candidate of those polled with 6%, while former Texas Rep. Beto O’Rourke and entrepreneur Andrew Yang each drew 2%.

The rest of the candidates in the crowded field, including the highly-visible New Jersey Senator Cory Booker, drew less than 1%support of those polled.

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