The White House is gearing up for a high-stakes fight over President Biden’s economic agenda following a major bipartisan victory Tuesday as the Senate passed a $1 trillion package to rebuild physical infrastructure with significant bipartisan support.

The 69-30 vote delivered a major victory for Biden amid broad skepticism that lawmakers from both sides of the aisle could come together on a massive spending bill. In the end, 19 Republicans joined all 50 Democrats.

The vote clears the way for what will be a weeks-long summer slog over the remainder of Biden’s agenda that Democrats are packing into a $3.5 trillion reconciliation package. At the same time, the bipartisan infrastructure bill will need to clear another hurdle to become law — namely, a House vote, and Speaker Nancy Pelosi (D-Calif.) has vowed to hold off on floor action until the lower chamber passes the bigger reconciliation package.

The White House will need to work to keep both moderates and progressives on board for the larger Democratic measure to ensure it can pass without any GOP support, while also maintaining public support for Biden’s legislative plans as Republicans look to make the $3.5 trillion bill a campaign issue in the midterm elections.

Biden administration officials are expected to traverse the country to tout Biden’s Build Back Better agenda over the next few weeks, with Transportation Secretary Pete Buttigieg traveling to Dallas and southern Nevada on Wednesday and Thursday to highlight the infrastructure bill’s spending on airports, roads and transit systems.

For now, White House press secretary Jen Psaki said Biden will be working the phones to speak with lawmakers to answer questions or address any concerns they might have about getting the infrastructure bill and the reconciliation package across the finish line.

As of last week, the White House legislative staff said it had participated in 375 meetings and calls with members of Congress and senior congressional staff regarding the reconciliation package alone.

Biden began his own victory lap on Tuesday at the White House after returning from a long weekend in Delaware.

“After years and years of infrastructure week, we’re on the cusp of an infrastructure decade that I truly believe will transform America,” Biden said in prepared remarks.

Current and former government officials acknowledge the path forward is likely to be challenging, particularly as the White House tends to a fractious House Democratic Caucus. Moderate and progressive members of Congress have already started to flex their respective muscles to get assurances about both bills in a sign of what lies ahead.

Leaders of the Congressional Progressive Caucus on Tuesday informed House leadership that most of their members indicated they will withhold votes on the bipartisan bill until the Senate passes its reconciliation package, in a bid to guarantee liberal priorities are passed as part of the two-track plan.

“Progressives are the ones that are tying these two bills together procedurally,” said Mary Small, national advocacy director for the progressive group Indivisible. “That is Biden’s best pathway to accomplishing so many of the pieces of the American Jobs and Families plans that weren’t included in the infrastructure bill.”

The Progressive Caucus has nearly 100 members, giving it significant leverage over the upcoming House proceedings.

At the same time, a group of moderate Democrats wrote to Pelosi on Tuesday stressing the need to pass the infrastructure bill as quickly as possible while raising concerns with “specific components” of the $3.5 trillion reconciliation package.

“His message is that he remains committed to passing each of these pieces of legislation on dual tracks,” Psaki told reporters when asked what Biden’s message to moderates is on how to sequence the two bills.

“He is going to work in lockstep with Speaker Pelosi just as we have worked in lockstep with [Senate Democratic] Leader [Charles] Schumer [N.Y.] successfully over the last several weeks and months to get this done,” Psaki said. “And he is confident in the leadership, the strategic approach of Speaker Pelosi and looks forward to being her partner in the weeks ahead.”

Biden on Tuesday would not say whether the House should quickly bring the bipartisan bill up for a vote, instead chuckling and vowing that both pieces of legislation would reach his desk.

“I continue to be an optimist,” Biden told reporters. “I think that we will get enough Democrats to vote for it and I think that the House will eventually put two bills on my desk.”

Senate committees are expected to spend the coming weeks hashing out the specifics of what will make it into the reconciliation bill, with climate provisions, drug costs and funding for education all on the table. If all goes smoothly, the House would be on track to potentially pass both the larger budget piece and the bipartisan infrastructure bill next month when lawmakers return to Washington.

“This administration, this Congress are going to have to do a bit of a balancing act to make sure that we are addressing, the extent to which we can within that topline, all of the key priorities around climate, around jobs, around equity that this administration has articulated forcefully,” said Jason Walsh, executive director of the BlueGreen Alliance, a coalition of major labor unions and environmental organizations that is pushing for investments in climate-friendly manufacturing and the care economy.

In the meantime, the White House will work to keep Biden’s economic agenda popular and fend off Republican attacks.

Celinda Lake, a leading pollster for Biden’s 2020 presidential campaign, said the White House should emphasize that the president has delivered on his promise to work across the aisle to deliver an infrastructure bill despite the broad skepticism he could do so. Administration officials should also highlight that Biden’s agenda impacts voters in specific, tangible ways, she added.

That means talking about how the infrastructure bill will expand access to high speed internet, repair roads and bridges and deliver clean drinking water, Lake continued, while focusing on investments in “human infrastructure” like child care access in the reconciliation bill that matter immensely to female voters.

“Painting a picture of really the visible changes this is going to produce,” she said.

Biden and Vice President Harris launched their sales pitch on Tuesday, describing what the bipartisan bill would mean for Americans.

They spoke of families no longer needing to siphon internet access by parking outside a fast food restaurant thanks to investments in broadband. They highlighted funding to replace lead pipes that create dangerous drinking water for children. And Biden pointed to “the most important investment in public transit in American history.”

Even though almost 20 Republicans voted in favor of the infrastructure package, the GOP is expected to be united against the $3.5 trillion package. Republicans have tried to brand the package as a “tax-and-spending spree.”

Lake said the White House can counteract Republican claims that the package will raise taxes by pointing out that it is paid for by tax hikes on corporations and the wealthiest Americans — which polls show are broadly popular.

“These packages are so big that there’s always a fight to define them,” Lake said, adding that the more Democrats can emphasize the tangible impacts on lives of average Americans, the less Republicans will be able to vilify the reconciliation package.