Terry McAuliffe had just won the Democratic nomination for governor in Virginia last month when he got a call from President Biden.

“Terry, I’m all in,” Biden told him. “What do you want?”

“I need you to come in and, you know, help campaign,” replied McAuliffe, who recalled the conversation in an interview.

“I’m there,” Biden replied.

Biden will make his first candidate-specific foray onto the campaign trail as president on Friday, a quick hop across the Potomac River to Arlington to stump for McAuliffe in the year’s marquee election, a contest that is stoking some Democratic nervousness. The race is shaping up as a pivotal first test of the appeal of Biden’s agenda, as well as whether the moderate, suburban-led coalition that propelled him into office will endure or evaporate in the post-Trump era.

“Virginia is a perfect petri dish for the president to test-drive his midterm and any reelection messaging,” said Dan Sena, former executive director of the Democratic Congressional Campaign Committee.

The central questions, said Sena — whose firm now works for Del. Hala S. Ayala of Prince William County, the Democratic nominee for lieutenant governor — are whether suburban voters are still driven by antipathy toward former president Donald Trump and how much they will credit Biden for his efforts to combat the pandemic.

Friday's event kick-starts what Biden’s friends and associates expect to be an aggressive schedule this election cycle as Democrats try to transcend the historical pattern of a president’s party getting pummeled in midterm elections.

“I think we’ll probably see a lot of him,” said Sen. Robert P. Casey Jr. (D-Pa.), a friend of Biden’s.

Virginia and New Jersey, which hold their gubernatorial elections in off-years, are often seen as bellwethers heading into the midterms. Operatives in both parties anticipate an easier Democratic victory in New Jersey, putting the spotlight squarely on Virginia — which has trended Democratic in recent years and is seen by the party as a must-win.

But injecting Biden into state and local campaigns also carries risks for Democrats. The president has long shown a tendency to veer off script, sometimes to the point of making distracting comments that require cleanup by him and his aides. And Biden's popularity, while steady, is not overwhelming, with many Republicans already turning against him.

Still, Biden enjoys few things as much as campaigning and has been watching the national landscape closely, according to people with knowledge of the situation. He has approached Democratic candidates to say he will campaign for them, even before they ask, according to people familiar with the conversations.

In March, Biden privately told Democratic senators how important he felt it was for them to expand their slim majority, according to a person with knowledge of the exchange. He helped raise money for the Democratic National Committee last month. And in May, he and DNC Chair Jaime Harrison held a private videoconference call to thank top donors, according to two people with knowledge of the gathering.

Biden, unlike his two predecessors, loves plunging into crowds and grasping voters by their shoulders or arms, an activity he has largely been denied by the pandemic.

“He enjoys working that rope line,” said Dick Harpootlian, a Democratic South Carolina state senator who has known Biden for three decades.

On the night in February 2020 when Biden won the South Carolina Democratic primary, Harpootlian grew concerned watching Biden shaking hands, since the coronavirus was already spreading. “We need to get him out of there,” he recalled telling then-campaign chairman Steve Ricchetti. But Biden refused to stop.

Barring changes to public health guidelines, the next 15 months will give Biden plenty of opportunities to hit the trail. Democrats are defending a 50-50 Senate in which Vice President Harris breaks ties, and some of the pivotal races are in places where his presence could help the party.

Six of the nine Senate races regarded by the nonpartisan Cook Political Report as most competitive are in states Biden won. And the path to preserving Democrats’ narrow House majority also runs through suburban districts that swung sharply toward Biden and his party during Trump's presidency.

The fate of Biden’s agenda in the second half of his term depends heavily on the midterms. Notably, Senate Minority Leader Mitch McConnell (R-Ky.) has suggested the Senate will probably not confirm any Supreme Court nominees for the rest of Biden’s term if Republicans retake the chamber.

Historically, first midterms have been rough for the president's party, with voters angry with the new direction of the country tending to be the most motivated to turn out. Democrats were wiped out in 2010, losing their House majority amid a backlash to President Barack Obama and his signature health-care law. In 2018, Republicans lost control of the House amid a similar turn against Trump.

Many Democrats say they view Biden, with his moderate political image, as less prone to becoming a such a divisive midterm influence. They note that Republicans in the early going have focused more fire on figures such as House Speaker Nancy Pelosi (D-Calif.), Sen. Bernie Sanders (I-Vt.) and Rep. Alexandria Ocasio-Cortez (D-N.Y.).

But Republicans say that does not mean a Biden visit would be an asset for a Democratic candidate.

“Ultimately, what's going to be a problem for Democrats is the Biden agenda,” said Chris Hartline, communications director for the National Republican Senatorial Committee, citing inflation and volatility at the border on Biden’s watch. “I think there are issues [on which] Biden can hurt Democrats across the country.”

Overall, Biden is in better political shape than Trump was at a comparable point in his presidency and is seen as less divisive, polls shows. But he is worse off at this point than Obama or President George W. Bush, a development some attribute to an increasingly polarized country.

The White House declined to make an official available to speak publicly for this report, but aides say they see Biden’s economic agenda, with its goals of equity and job creation, as a centerpiece of the party’s midterm pitch.

McAuliffe agreed that Biden’s agenda will strongly influence his race. “I think it’s a huge factor,” he said.

In a phone interview after a stop at a large retirement home — “Couple thousand of my voters out there!” McAuliffe boasted — he pointed to the significant role of the defense industry and federal workers in Virginia and touted the impact of Biden’s coronavirus recovery legislation. “When the federal government's working — functioning, unlike what Trump had for four years — it has a huge impact,” he said.

McAuliffe’s Republican opponent is Glenn Youngkin, a wealthy former private-equity executive who has been running ads in Northern Virginia about basketball and business, designed to introduce him as a friendly suburban dad. His emergence as the GOP nominee, prevailing over rivals to his right, is part of what has given Democrats some anxiety.

But Youngkin is supported by Trump, and before he won the GOP nomination he dodged questions about whether Biden had legitimately won the presidency, only later affirming Biden’s victory. The Youngkin campaign declined to say whether the Republican wants Trump to campaign with him.

McAuliffe’s first general-election television commercial, released Wednesday, contrasts his record with that of his rival, whom he calls “a loyalist to Donald Trump.”

What makes Virginia in many ways an ideal political testing ground for Biden’s midterm campaigning is its geographic makeup, including affluent suburbs, battleground exurbs, heavily African American areas and large stretches of rural terrain populated mostly by White voters.

Among the questions Biden is confronting are whether the Trump base will turn out when the former president is not on the ballot, whether Biden’s ambitious economic plans will be seen as a boon or a driver of rising prices and whether voters will continue to give the president high marks for his handling of the pandemic.

Republicans are highlighting the insider record of McAuliffe, a former governor and longtime friend of former president Bill Clinton and former secretary of state Hillary Clinton. “Terry McAuliffe must be worried about his terrible poll numbers if he's already calling in political favors this early in the campaign,” Youngkin spokeswoman Macaulay Porter said of Friday’s event.

McAuliffe’s emergence as the Democratic nominee is part of a larger trend of Democrats rallying around centrists in at least some races. In New York City, Democrats nominated Eric Adams, a former police officer running on a law-and-order platform, as their mayoral candidate. Biden has sought to steer the party away from championing controversial messages such as “Defund the police,” which some Democrats believe cost the party congressional seats in 2020.

On Friday, McAuliffe and Biden intend to discuss less polarizing topics, including job creation and health-care costs. The event is designed to look and feel like the gatherings that were standard on the campaign circuit before the pandemic shut them down last year.

Friday's stop will also serve as a test for how White House officials plan to protect the president amid growing concerns about the coronavirus delta variant and the recent infection of a vaccinated White House official.

The invitation sent to general audience members stated that attendees who are fully vaccinated will not have to wear masks, following the guidance of the Centers for Disease Control and Prevention, according to the White House. Those who are not fully vaccinated will be required to wear masks and stay six feet away from others in the audience.

Other issues could also arise as Biden kicks off a more campaign-oriented phase of his presidency. In 2019, Lucy Flores, a Nevada Democrat who once ran for lieutenant governor, accused Biden of kissing and touching her without her consent when he campaigned for her in 2014. Biden said he never believed he acted inappropriately but would listen with respect to suggestions that he had.

In an interview this week, Flores said she believes Biden has become “more aware” of how he comports himself physically. But she sees a limit to what Biden can accomplish politically in a state like Nevada, where Sen. Catherine Cortez Masto (D) is seeking reelection.

“To the extent that they are going to talk to their base, I think it will be effective,” Flores said. “To the extent that they are going to be able to expand that Democratic base, I don’t see that happening.”

Scott Clement contributed to this report.