A divided US Senate has blocked gun control measures, eight days after Orlando's mass shooting intensified pressure on senators to act.
In largely party-line votes, senators rejected one proposal from each side to keep extremists from acquiring guns, and a second aimed at shoring up the US government's system of required background checks for many firearms purchases.
With the chamber's visitors' galleries unusually crowded for a Monday evening - including relatives of victims of past mass shootings, some of whom wore orange T-shirts saying "#ENOUGH gun violence" - each measure fell short of the 60 votes required to progress.
Democrats called the Republican proposals unacceptably weak, while Republicans said the Democratic plans were too restrictive.
The stalemate underscored the pressure on each party to stand firm on the emotional gun issue going into November's presidential and congressional elections.
It also highlighted the potency of the National Rifle Association (NRA), which urged its huge and fiercely loyal membership to lobby senators to oppose the Democratic Bills.
"Republicans say, 'Hey look, we tried,'" said Senate Minority Leader Harry Reid. "And all the time, their cheerleaders, the bosses at the NRA, are cheering them."
Senate Majority Leader Mitch McConnell said the Orlando shootings - in which the FBI says the American-born gunman swore allegiance to an Islamic State group leader - show that the best way to prevent extremists' attacks here is to defeat them overseas.
"No-one wants terrorists to be able to buy guns," Mr McConnell said.
He suggested that Democrats used the day's votes "to push a partisan agenda or craft the next 30-second campaign ad".
The 49 victims who died in Omar Mateen's June 12 rampage at a gay nightclub made it the worst mass shooting in recent US history, topping a string of such incidents in recent years.
The FBI said Mateen - a focus of two terror investigations that were dropped - described himself as an Islamic soldier in a 911 call during the shootings. This allowed gun control advocates to add national security and the spectre of terrorism to their arguments for firearms curbs.
After the votes, presumptive Democratic presidential candidate Hillary Clinton issued a one-word statement, "Enough", followed by the names and ages of Orlando's victims.
On Fox News Channel's The O'Reilly Factor, Donald Trump said he "absolutely" agrees that people on the government's terror watch list should be barred from owning guns.
The presumptive Republican presidential nominee did not say if he supported the Republican or Democratic versions of the rejected bills.
Only a handful of politicians changed positions from votes cast last December on similar proposals, highlighting each party's enduring stances on guns. There is little sign that the House's Republican leaders will allow votes.
Even so, GOP senators facing re-election in swing states this autumn are finding themselves under extraordinary pressure.
One vulnerable Republican, New Hampshire's Senator Kelly Ayotte, backed both Bills blocking gun sales to terrorists, a switch from when she joined most Republicans in killing a similar Democratic plan last December. She expressed support for a narrower bipartisan plan, like one being crafted by Senator Susan Collins.
Ms Collins was trying to fashion a bipartisan Bill preventing people on the government's no-fly list from getting guns. She expressed optimism the Senate would vote on her plan, and Senator John Cornyn said that according to Mr McConnell, if Ms Collins wants a vote on her proposal, "She'll get one".
The votes came after Senator Chris Murphy led a near 15-hour filibuster last week demanding a Senate response to the Orlando killings.
Mr Murphy entered the Senate shortly after the December 2012 massacre of 20 young children and six staff in Newtown, Connecticut, but that slaughter and others have failed to spur Congress to tighten gun curbs.
The last were enacted in 2007, when the background check system was strengthened after the mass shooting at Virginia Tech.
No background checks are required for anyone buying guns privately online or at gun shows.