WASHINGTON – If the 2020 election was held this week, a new poll suggests President Donald Trump would likely lose to several top Democratic presidential candidates, including former Vice President Joe Biden.

According to a new national Quinnipiac poll, Biden holds a 13 percentage-point lead over Trump, 53% to 40%. In the Democratic primary race, Biden is currently the front-runner, with 30% of Democratic and Democratic-leaning voters surveyed in the poll saying they would vote for Biden.

The poll comes as Trump and Biden have repeatedly criticized each other over the past couple of weeks since the former vice president jumped into the 2020 race. Their barbs hit a crescendo Tuesday as the two campaigned in Iowa.

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However, Biden is not the only 2020Democrat who comes out ahead of Trump in a head-to-head matchup in the national poll.

Sen. Bernie Sanders, I-Vt., has a 9 percentage-point lead over Trump, 51% to 42%. Sen. Kamala Harris, D-Calif., is holding an 8-point lead, at 49%, compared to Trump's 41%. Sen. Elizabeth Warren, D-Mass., tops Trump with a 7 percentage-point lead at 49% to 42%. Both South Bend, Indiana, Mayor Pete Buttigieg and Sen. Cory Booker, D-N.J, hold a 5 percentage-point lead against Trump, with each at 47% to Trump's 42% in both of those matchups.

The survey's results for many of the head-to-head matchups are outside the margin of error, which is plus or minus 3.5 percentage points. Quinnipiac University surveyed 1,214 voters nationwide from June 6 to June 10. The poll includes 503 Democrats and Democratic-leaning voters who were surveyed, with a margin of error of plus or minus 5.4 percentage points.

In the Democratic primary race, after Biden's 30%, Sanders has 19% among Democratic and Democratic-leaning voters. Warren was the only other candidate to poll in the double digits at 15%. Buttigieg follows at 8% and Harris at 7%. Former Texas Rep. Beto O'Rourke is at 3%. No other Democrat topped 1%; in fact, 14 candidates in the large Democratic 2020 field polled at less than 1%.

Although he remains the front-runner in the Democratic primary race, the poll reflects a drop for Biden. In a May 21 poll, he was at 35% and at 38% in an April 30 poll.

As Biden slips, other major Democratic candidates are continuing to gain, according to the poll.

Just last month, Sanders was at 16%, Warren was at 13%, and Buttigeig was at 5%. Harris dropped 1 percentage point from last month, when she was at 8%.

These latest national results mirror a similar trend in Iowa, where the former vice president's polling numbers are also slipping, while other major candidates are growing their support in the 2020 Democratic primary race.

According to a recent Des Moines Register/Mediacom/CNN Iowa Poll, 24% say that Biden is their first choice for president. That number has dropped since March, when he was at 27%. In a December Iowa poll, Biden was at 32%.

Just like they are nationally, Warren and Buttigieg have all seen an increase in voter support in Iowa. Warren in March was at 9%. However, in the latest Iowa poll she was at 15%. Buttigeig was only at 1% in March and has since reached 14% in Iowa.

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Although Trump is trailing in a number of head-to-head matchups against 2020 Democrats, his job approval rating is one of the highest Quinnipiac has seen in its surveys.

Trump's job approval rating is at 42%, with disapproval at 53%. In a May 2 Quinnipiac poll, Trump's approval was at 41% while his disapproval rating was at 55%.

The poll comes nearly a week after a separate Quinnipiac poll showed the president in a tight race against several Democratic candidates in Texas, a traditionally conservative-leaning state.

Biden is in a tight head-to-head matchup with Trump in Texas, with the former vice president at 48% to Trump's 44%, according to a Quinnipiac University poll published last week. The president was also locked in too-close-to-call matchups with six other Democratic 2020 presidential candidates, including Warren, Sanders, O'Rourke, Buttigieg, Harris and former San Antonio, Texas, Mayor Julian Castro.

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