“Is this my homecoming?” Joe Biden asked a throng of journalists in passing as he made his way to a luncheon just off the Senate floor.

The president on Wednesday made his first work trip back to the chamber where he spent 36 years of his life to unite his party around a plan to authorize $3.5 trillion in all sorts of new spending on health care, education, clean energy and affordable housing through a filibuster-proof budget reconciliation package — while simultaneously passing a bipartisan infrastructure deal.

If Biden and congressional Democrats pull this off, they’ll approve $4.1 trillion in new spending, more than double the size of the tax cuts that Donald Trump and congressional Republicans managed to ram through in 2017.

To do it, Biden will need every single one of the 50 Senate Democrats to go along with the framework crafted by Majority Leader Charles E. Schumer and the Budget Committee — hence, the midweek visit for lunch.

As is so often the case with presidents, Biden was late.

“Where is he?” Schumer asked his security detail and staff around 12:40 p.m. A half-hour would pass before the president arrived for the meeting scheduled for 12:45 p.m.

Across town, Olivia Rodrigo was playing press secretary at the White House, but for denizens of Capitol Hill, no pop singer can hold a candle to a president’s star power.

More than two dozen interns and staffers gathered in the hallways outside the Mansfield Room shortly before Biden’s arrival. As the presidential motorcade made its way down Pennsylvania Avenue, the gaggle was pushed by security officers down past Minority Leader Mitch McConnell’s office. But the giggling group continued to chat and hold their phones, taking photos of the building’s architecture and each other as they waited for the chance to catch a glimpse.

Some even got down on their knees to get the perfect shot as the moment arrived. Down the hallway, a flutter of camera shutters clicked, signaling the president’s arrival.

“That was so cool,” an intern cheered as a very distant Biden slipped in and out of their line of sight.

“I got a good one of him,” one said.

“Can you send me those?” asked another.

And then they were gone, back to their respective offices with a photo and a story about how they once saw the president of the United States of America.

Over grilled chicken and green beans, Biden made his case to the caucus. For the plan to work, not a single Democratic senator can vote no, effectively giving each a veto power.

He already has the support of the chamber’s leading progressive, Bernie Sanders, the self-styled democratic socialist who chairs the Senate Budget Committee. “It is the most transformative bill for working people that we’ve seen since the 1930s,” Sanders told reporters.

Instead, all eyes are on Sens. Joe Manchin and Kyrsten Sinema, who thus far into Biden’s presidency have been the Democrats most willing — and sometimes downright eager — to buck the party line.

Manchin told reporters after the luncheon that he needs to see more details, especially on how the bill treats fossil fuels, before he could support it. But he struck mostly positive notes.

“I think the president gave a very good presentation,” the West Virginian said. “He understands this process. … He spent 36 years [in the Senate], he knows how it works.”

“The president made a really compelling case for both packages,” said Sen. Chris Murphy of Connecticut. “He just kept on telling us to think about his neighbors in Scranton, to think about whether what we’re doing is going to pass muster with the folks that he grew up with.”

“We’re making progress,” said Schumer. “It’s a long hard road but we’re making good progress.”

While the White House has worked closely with the Budget Committee and Schumer on the framework for the massive spending deals, Biden has avoided dominating the public debate around it, the way presidents often can, inadvertently or not, with their bully pulpit. As he did with the $1.9 trillion COVID-19 relief bill Congress passed through reconciliation earlier this year, Biden initiated the conversation by laying out broad legislative goals, but then let the Senate — and, to a lesser extent, the House — take the lead in negotiating a pathway to passage.

And so, it was Schumer, Sanders and Sen. Mark Warner who announced the $3.5 trillion agreement among the Budget Committee Democrats on Tuesday, and it was Biden supporting them in convincing the rest of the caucus on Wednesday.

Nearly an hour after he entered the Mansfield Room, Biden left to extended applause.

“That was a thank you to him for being here,” said Sen. Jeanne Shaheen of New Hampshire.

Biden walked back past the press again, barely slowing down to wax nostalgic. “It’s great to be home,” he said, declining to take questions. “Great to be back with all my colleagues. And I think we’re going to get a lot done.”

It’s hard to overstate how deep Biden’s ties are to the Senate, the chamber he technically, constitutionally, presided over during his two terms as vice president. The luncheon was held in the Mansfield Room, a name with significance. When Biden’s wife and newborn daughter were tragically killed shortly after his election in 1972, it was then-Majority Leader Mike Mansfield who helped convince Biden to take office anyway. “Mansfield would not give up on me. He kept calling to check on me,” Biden wrote in his 2007 memoir.

Since his inauguration on the Capitol’s east front, Biden has mostly stayed away from the Hill. He made an informal visit in February to pay respects to fallen Capitol Police officer Brian Sicknick, who died after defending the Capitol from a mob of Trump supporters attempting to disrupt the certification of the 2020 election.

By the time Biden finished his meeting on Wednesday, a new crowd of interns and staffers crowded by the back doors of the Capitol.

“Was that him?” they asked each other as he left.

“That was it?” one said.

“That was amazing!” said another.

Lindsey McPherson, Jessica Wehrman and Bridget Bowman contributed to this report.