The US Senate voted Thursday to debate the nation's most ambitious gun safety legislation in almost two decades, after a bipartisan group of lawmakers agreed on expanding background checks.
As relatives of the 20 children killed in the Newtown massacre watched from the visitors' galleries, years of Senate refusal to address gun laws in the United States was swept aside, along with recent Republican obstruction.
Some 16 Republicans joined the Democrats, setting up crucial votes next week on amendments to a bill that would tighten checks for firearms buyers, stiffen penalties for gun trafficking and boost school safety measures.
"The hard work starts now," top Democrat Harry Reid told his Senate colleagues after the 68-31 vote.
White House spokesman Jay Carney said the "bipartisan progress" was encouraging, but stressed it was just the "first stage in an effort to get sensible, common-sense legislation."
President Barack Obama has leaned heavily on Congress to adopt his proposals after the December tragedy in Connecticut. He called families of the Sandy Hook school shooting victims to congratulate them on the vote result and pledge his continued support in the fight.
Jillian Soto, sister of slain Newtown first-grade teacher Victoria Soto, said she had hoped for a tougher background check amendment.
But "I'm happy that we are getting somewhere," said Soto, who spent days pressing lawmakers on Capitol Hill to enact tighter gun laws.
The key ingredient in the complex gun control recipe is the compromise on background checks reached by Democrat Joe Manchin and Republican Pat Toomey.
The deal waters down the universal background check system sought by Obama, which was opposed by scores of lawmakers, including some Democrats from pro-gun states.
But it strengthens existing law, which only requires background checks for firearm purchases at licensed gun dealers, to require checks for sales at gun shows and online. It would still allow gun sales between relatives and friends to continue without such safeguards, however.
"The bill will not, in any way, shape or form, infringe upon anyone's Second Amendment rights to keep and bear arms," Manchin said in a statement after publishing the text when Reid put the measure on the schedule for next week.
"The bill will not take away anyone's guns," Manchin insisted, in an effort to tamp down Republican concerns that the legislation will erode gun rights.
And the bill "will not create a national (gun) registry; in fact, it explicitly prohibits it," he added.
The big question now is whether the legislation, in part or as a whole, can pass the Senate and then the House, where an even tougher vote is expected.
Senate Republican Mark Kirk helped craft the compromise and is likely on board. Another party moderate, Susan Collins, expressed her initial support but said she wants to study the bill's language.
But conservative Senator Mike Lee took to the floor in opposition, reading letters from Americans who he said were "very concerned about Congress enacting any new gun control measures."
In a sign of the political heat, two Democrats facing re-election in 2014 in pro-gun states, Mark Pryor of Arkansas and Mark Begich of Alaska, voted against starting debate on the bill.
Reid has pledged to allow any senator to come forward with amendments to what is seen as the most significant US gun legislation since a 1994 federal crime bill.
He told colleagues to prepare for a series of tight votes on contentious amendments such as a proposed assault weapons ban, which is supported by Obama but is widely seen as unlikely to pass Congress, and a measure to limit high-capacity magazines.
House Speaker John Boehner said that if the Senate passes a bill, he would send it to the Judiciary Committee "for an open hearing," but he stopped short of assuring it would get a floor vote.
"Our hearts and prayers go out to the families of these victims, and I fully expect that the House will act in some way, shape or form," Boehner said.
"But to make a blanket commitment without knowing what the underlying bill is I think would be irresponsible on my part."
Meanwhile, freshman Senator Chris Murphy of Connecticut praised the Senate's move, but acknowledged the political crunch comes when the gun votes begin next week.
"I think love won this week," he said. "Our hope is that love wins next week as well."