The Senate passed the Bipartisan Safer Communities Act by a wide bipartisan margin on Thursday.
15 Republican senators supported the bill, which would enact the toughest new gun restrictions since the 1990s.
The bill would close the "boyfriend loophole," support state-level "red flag" laws, and makes new mental health investments.
The US Senate approved a bipartisan bill to enact new gun restrictions by a 65-33 vote on Thursday, with 15 Republicans joining every Democratic senator in support.
The Bipartisan Safer Communities Act, the full text of which can be found here, includes multimillion dollar investments in mental health services and school security, as well as a new federal ban on gun trafficking.
"We are passing the first significant gun safety bill in nearly 30 years," Senate Majority Leader Chuck Schumer said Thursday ahead of the vote, adding that the bill is "not a cure-all for all the ways gun violence affects our nation, but it is a long overdue step in the right direction."
The gun safety bill would offer new funding supporting states and tribes that seek to enact "red flag" laws - which allows authorities to confiscate guns from individuals deemed a threat to themselves or others - closing the so-called "boyfriend loophole, and subjecting gun purchasers under the age of 21 to new background check requirements.
"Our schools should be a sanctuary for our children, not a place where they plan what will happen during the next shooting and how they can hide under their desks or try to make their escape," GOP Sen. John Cornyn of Texas said on the Senate floor. "Schools should be a sanctuary, and this bill will provide the kind of services that will help identify students in crisis and help intervene to provide them the assistance they need."
He added: "We probably can't eliminate human error like we saw in Uvalde, Texas, but we can promulgate the best practices, which we have done in this bill."
The National Rifle Association announced their opposition to the bill within an hour of the text's release, and House Republicans cited the group's opposition as it urged their members to vote against the bill when it comes to the House.
But the bill is expected to easily pass in the House, even with some Republican support, and it will later head to President Joe Biden's desk.
The White House released a statement on Thursday indicating that Biden "strongly supports" the bill.
"While the Bipartisan Safer Communities Act does not include additional important steps the President has called for as part of his comprehensive gun crime reduction agenda, it would make meaningful progress to combat gun violence," read the statement. "As communities continue to experience gun violence every day, the Administration calls for swift passage of this life-saving legislation.
The bill was supported even by Senate Minority Leader Mitch McConnell, on top of the 10 Republican senators who endorsed a framework of the bill released last week. Following the Thursday vote, Schumer was seen giving McConnell a pat on the shoulder.
But four more Republicans - including Sens. Joni Ernst of Iowa, Todd Young of Indiana, Lisa Murkowski of Alaska, and Shelley Moore Capito of West Virginia - came out in support of the bill this week, voting to advance it in a procedural vote on Tuesday.
Here are the Republican senators who supported the bill:
Sen. Mitch McConnell of Kentucky
Sen. John Cornyn of Texas
Sen. Roy Blunt of Missouri
Sen. Richard Burr of North Carolina
Sen. Shelley Moore Capito of West Virginia
Sen. Bill Cassidy of Louisiana
Sen. Susan Collins of Maine
Sen. Joni Ernst of Iowa
Sen. Lindsey Graham of South Carolina
Sen. Lisa Murkowski of Alaska
Sen. Rob Portman of Ohio
Sen. Mitt Romney of Utah
Sen. Thom Tillis of North Carolina
Sen. Pat Toomey of Pennsylvania
Sen. Todd Young of Indiana
"I've talked to even Republican lawmakers in the state of Iowa, and they're like, 'We're hearing from our constituents too, about this issue,'" Ernst, a member of Senate Republican leadership who came out in support of the bill this week, told The New York Times. "So I think people recognize something needs to be done."