Former Vice President Joe Biden bests President Donald Trump by nine points in a 2020 ballot test, in the first Fox News Poll since Biden became the de facto Democratic nominee.

In a head-to-head presidential matchup, Biden is up by 49-40 percent over Trump, a lead that is outside the poll’s margin of sampling error. Another 11 percent would vote for someone else or are undecided. Last month, Biden was ahead by 49-41 percent.

The race remains a nine-point advantage for Biden over Trump when looking only at those voters extremely interested in the election (52-43 percent) and the former vice president has an eight-point edge in battleground states (48-40 percent).

However, Biden’s advantage grows to 25 points, 57-32 percent, in close counties (where Hillary Clinton and Trump were within 10 points in 2016).

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“Since our last poll, Biden has won enough delegates to make him the presumptive Democratic nominee, but the horserace has not budged. This might be a bad sign for Biden since he has received extensive and largely positive news coverage over the last month,” says Democratic pollster Chris Anderson, whose firm conducts the poll with Republican Daron Shaw.

“But there appears to be a modest rallying to the flag effect in response to the pandemic that is rewriting our political and social landscape in still unknown ways.”

In the matchup, Biden is the choice among liberals, non-whites, moderates, suburban women, and voters ages 65 and over.

Trump leads among conservatives, white evangelical Christians, those who attend religious services regularly, white men, and whites without a college degree.

Meanwhile, by a three-to-one margin, voters like Biden’s commitment to choose a woman as his running mate. Overall, 63 percent approve of his promise to pick a female, while 20 percent disapprove (17 percent unsure). There is no gender gap, but voters under age 45 are 10 points more likely than those ages 45 and over to approve (70 vs. 60 percent). Among Democrats, approval climbs to 86 percent.

Vetting of possible Democratic vice presidential candidates will reportedly start soon. The poll asks about the three female senators who also ran for the party’s nomination -- Kamala Harris, Amy Klobuchar, and Elizabeth Warren.

A Biden-Warren ticket bests Trump-Pence by 10 points and is the only ticket tested that puts the Democrats over the 50 percent threshold, 52-42 percent.

The Trump-Pence ticket also trails both Biden-Klobuchar and Biden-Harris tickets by 8 points (both 50-42 percent). The Democratic edge in all three matchups is outside the poll’s margin of sampling error.

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“The conventional wisdom is that vice-presidential picks don’t have much of an effect on the national vote,” says Shaw. “That seems to hold true in these early ballot tests. What’s less obvious is whether there might be some influence within certain states or whether a specific candidate could deliver a strong convention or debate performance.”

Pollpourri

Both Democrats (80 percent) and Republicans (83 percent) believe the outcome of the November election will be “very” important to the direction of the country.

Overall, 79 percent of voters feel the election will be “very” important. That’s up from 60 percent who felt that way just weeks before the 2014 midterm elections (October 2014), the only other time the question was asked on a Fox News poll.

In the midst of the coronavirus pandemic, over half of voters, 53 percent, are “extremely” interested in the presidential election. That is about where interest stood in January and February (both 55 percent extremely interested).

Conducted March 21-24, 2020 under the joint direction of Beacon Research (D) and Shaw & Company (R), this Fox News Poll includes interviews with 1,011 randomly chosen registered voters nationwide who spoke with live interviewers on both landlines and cellphones. The poll has a margin of sampling error of plus or minus three percentage points for all registered voters.