Washington — The House saw a rare moment of bipartisanship late Wednesday when lawmakers approved a major tax bill that would expand the Child Tax Credit and extend some business tax breaks. But whether the Senate can maneuver the legislation to passage is another question.

The bill passed the House by a vote of 357 to 70, earning more support from Democrats than Republicans. Next up is the Senate, where 60 votes would be needed to send the bill to President Biden's desk.

Senate Finance Committee Chairman Ron Wyden, an Oregon Democrat, and House Ways and Means Committee Chairman Jason Smith, a Missouri Republican, unveiled an agreement on the legislation last month. They celebrated what they called a "common sense, bipartisan, bicameral tax framework" that they said will "promotes the financial security of working families, boosts growth and American competitiveness, and strengthens communities and Main Street businesses."

"If Jason Smith and Ron Wyden can agree on something to this degree, that's this complicated, I start with the notion that it's certainly serious and we'll take a look at it," Sen. Kevin Cramer, a North Dakota Republican who said he's undecided on the bill, told reporters at the Capitol on Thursday.

Senate Majority Leader Chuck Schumer reiterated on Wednesday that he supports the bill, and said he's working with Wyden to determine the "best way forward."

The legislation, known as the Tax Relief for American Families and Workers Act of 2024, would enhance the Child Tax Credit to provide relief to lower-income families. The enhancement is smaller than a pandemic-era increase but it could still lift at least half a million children out of poverty, according to the Center on Budget and Policy Priorities. 

Nevertheless, opposition is expected from some Senate Republicans who have expressed concerns about the cost and the possibility of bolstering Mr. Biden's reelection bid. And on the left, some progressives are also expected to oppose the legislation in its current form, arguing that it doesn't go far enough to support low-income Americans.

Sen. Mitt Romney, a Utah Republican, told reporters on Thursday that he's "not inclined" to support the bill, noting that while he supports the tax provisions, he doesn't support "adding a new entitlement that's going to end up costing about $800 billion over a decade."

The bill that passed the House would expand the credit for three years at a cost of roughly $33 billion, according to the Congressional Budget Office. The Committee for a Responsible Federal Budget estimated in November that an earlier version of the package would have cost about $825 billion over the course of 10 years if the tax breaks were made permanent. But the final deal included various offsets to pay for the tax breaks, and the CBO estimates it would have little impact on the deficit over the next decade.

Republican Sen. Chuck Grassley of Iowa also reportedly expressed reservations about approving the bill during an election year.

"I think passing a tax bill that makes the president look good, mailing out checks before the election, means he could be reelected and then we won't extend the 2017 tax cuts," he said Wednesday, according to Semafor, referring to a looming fight over Trump-era tax breaks, many of which are set to expire in 2025.

Sen. Angus King, a Maine independent, said he thinks the legislation will have "good support" across the chamber, calling it a "good bill" negotiated on a bipartisan basis.

Cramer noted that "perfect can't be the enemy of good," pointing positively to the tax benefits for businesses while saying that the child tax credit elements could be tightened up. 

"But when there's enough for everybody to like most of it and enough for at least several to not like parts of it, it looks like a bipartisan deal," Cramer added.

The bill would make it easier for more families to qualify for the Child Tax Credit, along with increasing the amount from $1,600 per child to $1,800 in 2023, $1,900 in 2024 and $2,000 in 2025. It would also adjust the limit in future years to account for inflation. 

Adding to the possible roadblocks to the bill's passage in the upper chamber is its already busy agenda. Senate negotiators have for months been embroiled in talks over a border security agreement tied to a supplemental funding bill. Lawmakers expect that agreement to come out any day, which would likely spur floor action that would occupy the chamber's time. 

Congress is also heading toward a funding cliff, with deadlines to stave off a government shutdown next month. And a possible trial, should the House vote to impeach Department of Homeland Security Secretary Alejandro Mayorkas, could further limit the Senate's availability to take up the tax bill.

Kaia Hubbard

Kaia Hubbard is a politics reporter for CBS News Digital based in Washington, D.C.