Democrats demanding action on gun control continue to stage a sit-in on the floor of the US House of Representatives with one saying she would stay "until hell freezes over".
Unyielding Republicans who control the chamber have branded the move a publicity stunt and summarily adjourned the chamber.
Some 20 hours after the protest commenced - around a dozen Democrats remained, including minority leader Nancy Pelosi, giving speeches that mixed victory declarations with vows to never back down in their drive to curb firearm violence.
Texas representative Al Green said: "While the Americans don't always expect us to win, they do expect us to fight. We demonstrated to the American why we can't get votes on common sense safety measures."
When Republicans streamed to the exits hours earlier, Democrats remained on the House floor, shouting "No bill no break" and waving papers with the names of gun victims written on them. California representative Maxine Waters said she was ready to stay "until Hell freezes over".
With a crowd cheering them on from outside Washington and many more following the theatrics on social media, Democrats declared success in dramatising the argument for action to stem gun violence.
"Just because they cut and run in the dark of night, just because they have left doesn't mean we are taking no for an answer," Ms Pelosi.
Republicans fiercely resisted the Democratic pressure, saying their colleagues had accomplished nothing other than disrupting the business of the House to score political points. House Speaker Paul Ryan called it "a publicity stunt".
Georgia representative John Lewis said Democrats had "crossed one bridge" and "have other bridges to cross". He said Democrats "made a down payment on ending gun violence" in America.
At one point overnight, the two sides nearly came to blows after Republican Louie Gohmert of Texas approached the Democrats shouting: "Radical Islam!" Democrat Corrine Brown shouted back. The two came within inches of each other, both shouting, and were separated by colleagues.
Pressure had been building on both sides of the capital in the wake of the shooting rampage at a Florida gay nightclub earlier this month that killed 49 people and injured 53 others. The assailant also died in the incident. The mass shooting followed similar tragic incidents over the past years including the school shooting in Newtown, Connecticut.
The agitation for action caused a Senate filibuster last week and led to the chaos on the House floor that lasted well into Thursday.
The spectacle captured the attention of a Washington gridlocked on guns despite the slaughter in Orlando. Senate Democrats undertook a nearly 15-hour filibuster last week in fighting for the same cause.
House Republicans used their prerogatives as the majority party to muscle through a partisan bill funding the Zika crisis with no time for debate, overruling Democrats' objections and then moving to adjourn the house into next month amid protests from Democrats.
Republicans shut off the cameras in the House gallery throughout most of the protest, but Democrats used their mobile phones to capture the action, and satellite TV network C-Span carried the feeds live in an unprecedented move.
Mr Ryan said the bills pushed by Democrats, to expand background checks and keep people on the no-fly list from getting guns, would take away people's constitutional rights and deprive them of due process, and he noted similar legislation was already rejected in the Senate earlier in the week.
The protest began at around 11.30am on Wednesday, unfolding on the House floor with little advance warning from the Democrats.
By evening, 168 House Democrats - out of 188 - and 34 Senate Democrats joined the protest, according to the House minority leader's office.
Scattered around the House floor were signs reading "Disarm Hate". A crowd of several hundred gun control advocates gathered outside the capital and cheered as Democrats addressed them.
The sit-in - in which Mr Lewis played a leading role - had the look of a 1960s-style protest, as some politicians sat on the floor, others in their seats.
Republicans had staged a similar protest in 2008. Democrats controlling the House at the time turned off the cameras amid a Republican push for a vote to expand oil and gas drilling.
Republicans occupied the floor, delivering speech after speech after Ms Pelosi, then the House speaker, sent lawmakers to their August recess. Ms Pelosi at that time had ordered the cameras turned off.
C-span does not control the cameras. They are run on authorisation by legislative leaders. Although the cameras were turned off on Wednesday, representatives relied on social media to transmit video, using Facebook, Twitter and Periscope.
C-Span broadcast live video streamed on Periscope and Facebook from politicians' accounts.
Democrats posted the capital's main telephone number, which was overwhelmed, and urged constituents to call and request a vote. They also encouraged tweeting under the hashtag #NoBillNoBreak.