A proposed ban on assault weapons like the one used in an elementary school massacre last year has been removed from a broader gun control package, with Democrats conceding it would not get through Congress.
The move by Senate Majority Leader Harry Reid does not kill the proposal outright. But separating it from three other measures being strongly pushed by President Barack Obama's Democrats leaves it to wither in today's highly partisan Congress.
Reid said the ban on assault weapons and high-capacity magazines, proposed in the wake of December's mass murder of 20 school children and six staff in Newtown, Connecticut, did not have the votes to pass.
Democratic Senator Dianne Feinstein had tabled the ban, and it had won support from many in her party, but not enough fellow senators to pass the 100-member chamber.
"Right now her amendment, using the most optimistic numbers, has less than 40 votes," Reid said. "I have to get something on the floor so we can have votes on that issue."
Controversial bills need 60 votes to ensure that they are not derailed by a filibuster, a parliamentary maneuver to prevent them coming to a vote.
Democrats, who hold 55 Senate seats, had sought Republican support for four measures, including that background checks be required for all gun sales, which they hoped to cobble together into one bill.
The other three measures have a chance of winning some modest Republican support and have somewhat better odds of getting through both houses of Congress.
The assault weapons ban, backed by the White House, passed out of committee last week on a strict party-line vote.
It still could be voted on separately, and while that would be expected to fail, Feinstein was standing firm about demanding Reid allow her such a vote.
"I'm not going to lay down and play dead," she said on CNN. "I think the American people have said in every single public poll that they support this kind of legislation."
Not allowing her a floor vote on her measure "would be a major betrayal of trust," she said, noting that Reid told her she would have an opportunity for a floor vote.
But the ban's lukewarm support among Democrats was "the handwriting on the wall," Republican Senator James Inhofe told AFP.
Inhofe said he now believed "zero" bills tightening gun laws would pass Congress this year.
"Some could pass the Senate, but not the House," which is controlled by Republicans who are less supportive of legislation that could be seen as curtailing American's Second Amendment right to bear arms.
There is also some pushback from Democrats in rural states where guns are popular for hunting and sport.
Democratic Representative Mike Thompson, who chairs the House Gun Violence Prevention Task Force, said Reid's move was not surprising, and that Feinstein "knew all along it was going to be an extremely heavy lift."
Gun violence prevention is fraught with sensitivities, Thompson said, particularly when lawmakers use tragedy to drive home a political agenda.
"The issue is volatile. Even the slightest hint of using the wrong vernacular" creates problems, he said.
As for a way forward, "we need to prioritize... commonsense reforms," Thompson said.
The Feinstein measure would have prohibited the manufacture, import and sale of 157 models of assault weapons, including the one used on December 14 to kill 20 schoolchildren and six adults at Sandy Hook Elementary School.
It would have been a reprisal of her 1994 assault weapons ban, which only squeaked through Congress because it included a sunset provision that caused it to expire in 2004.
In part, Feinstein blamed her bill's woes on the money and political power of the main US pro-gun lobby, the National Rifle Association.
"America has to stand up," she said. "I can't fight the NRA. The NRA spends unlimited sums, backed by the gun manufacturers, who are craven in my view."
The Brady Campaign to Prevent Gun Violence said in a statement that "we continue to believe in the comprehensive set of reforms put forth by the president," and stressed that all four measures that passed through committee, including the assault weapons ban, "should be part of the solution" to gun violence.
But Alan Gottlieb of the Second Amendment Foundation said there was never enough congressional support for Feinstein's ban, especially given how many Democrats who supported the 1994 ban subsequently lost their seats in Congress.
"I think Democrats are taking a look at the demographics and the electorate," Gottlieb said.
"They know the number of seats they have up in the next election, and if they pushed that bill through, the Senate would change hands."