Senate Democrats said late on Tuesday they had reached a budget agreement that envisions spending an enormous $3.5tn over the coming decade, paving the way for their drive to pour federal resources into climate change, healthcare and family service programs sought by Joe Biden.

It is a major step in the party’s push to meet the president’s goal of bolstering an economy ravaged by the coronavirus and setting it on course for growth. It includes a Medicare expansion of vision, hearing and dental benefits for older Americans, a goal of progressives.

But Democrats behind the agreement face possible objections from moderates and progressives and will have to work hard to convert their plans into legislation they can push through the closely divided Congress over probably unanimous Republican opposition.

“We are very proud of this plan,” the Senate majority leader, Chuck Schumer, told reporters. “We know we have a long road to go. We’re going to get this done for the sake of making average Americans’ lives a whole lot better.”

Biden will attend a closed-door lunch at the Capitol on Wednesday with Senate Democrats to focus on “getting this wonderful plan” enacted, Schumer said.

The proposal reflects Biden’s vision for making the most substantive investments in the nation in years, some say on par with the New Deal of the 1930s. Together with a slimmer, $1tn bipartisan effort of traditional road, highway and public works also being negotiated, they represent close to the president’s initial $4tn-plus effort that could reach almost every corner of the country.

The Democrats’ goal is to push a budget resolution through the House and Senate before lawmakers leave for their August recess. The resolution sets only broad spending and revenue parameters, leaving the actual funding and specific decisions about which programs are affected for later legislation.

Nonetheless, approving a budget will be a major boon for Democrats’ effort to enact their subsequent funding bill. That’s because the budget contains language that would let Democrats move the follow-up spending measure through the 50-50 Senate with just a simple majority, not the 60 votes Republicans could demand by using a bill-killing filibuster.

The actual spending legislation will likely not start moving through Congress until the fall.

Separately, a bipartisan group of senators is working to flesh out a measure that would spend around $1tn on roads, water systems and other infrastructure projects, another Biden priority. Biden and that group had agreed to an outline of that measure last month.

On Wednesday, Biden will push for public support of that infrastructure proposal by hosting a bipartisan group of governors and mayors at the White House. He plans to emphasize the bipartisan aspects of the proposal, as senators work to finalize details for a Thursday deadline.

He’ll highlight some of the areas where Democrats and Republicans agreed, including investments in removing lead pipes, expanding access to high-speed internet, transit and rebuilding roads and bridges. Biden will also speak about the impact his policies would have on local communities, according to an administration official.

Schumer and other lawmakers did not respond when asked if they had the support of all 50 Democratic senators. They have virtually no margin for error in the House, where they can lose no more than three votes and still prevail.

Senator Bernie Sanders, the budget committee chairman, and other progressives pushed for a $6tn budget top line, while moderates insisted on a far lower price tag. Biden had proposed about $4.5tn.

The Democrats’ announcement left many questions unanswered. These included how much it would raise through tax increases on the wealthy and corporations and other revenue to pay for its costs; how much would be spent on specific programs; and how Biden’s proposals would be curtailed or eliminated to fit into the legislation.

Schumer said the proposal would call for financing Biden’s budget priorities “in a robust way”.

Sanders said the agreement would end an era in which rich people and big companies weren’t bearing enough of the burden of financing government programs.

“Those days are gone,” he said. “The wealthy and large corporations are going to start paying their fair share of taxes, so that we can protect the working families of this country.”

Mark Warner of Virginia, a leading moderate who helped shape the budget package, said the measure would be fully paid for with offsetting revenue, but provided no details. Biden has proposed financing the measure with higher taxes on the wealthy and corporations and collecting more revenue via the Internal Revenue Service.

The budget will include language calling for no tax increases on people making less than $400,000 a year, a Biden demand, or on small businesses. The provision was described by a Democratic aide.