As compromise on the gun issue remained improbable, Senator Chris Murphy stood on the Senate floor for most of Wednesday and into Thursday, saying he would remain there "until we get some signal, some sign that we can come together."
He yielded the floor at 2:11 a.m., saying he had won commitments from Republican leaders that they would hold votes on amendments to expand background checks and ban gun sales to "suspected terrorists".
Murphy spent much of the time speaking about the shooting at Newtown, Connecticut's Sandy Hook Elementary School in December 2012.
He finished the filibuster with a large picture of 6-year-old Dylan Hockley who was killed in the shooting.
"Dylan was struggling with autism as a student at Sandy Hook elementary school. But he was a special, special boy who was going to turn in to a special, special young man. He idolized his brother Jake. But he idolized someone else as well. He idolized a woman named Ann Marie Murphy. Ann Marie Murphy was his special education teacher and his personal aide," Sen. Murphy said.
Senator Murphy spoke of Dylan's teacher finding the 6-year-old during the shooting.
"Instead of panicking, Anne Marie Murphy found Dylan Hockley and embraced him. You know why we know that? Because when the police entered the classroom, that's how they found Dylan Hockley, dead, wrapped in the embrace of Anne Marie Murphy," Sen. Murphy said.
"It takes courage to look into the eye of a shooter, and instead of running, wrapping your arms around a 6-year-old boy and accepting death as a trade for just a tiny little itty piece of increased peace of mind for a little boy under your charge. And so this has been a day of questions. And so I ask you all this question, 'If Anne Marie Murphy could do that, then ask yourself, what can you do to make sure Orlando or Sandy Hook never, ever happens again?' With deep gratitude to all those who have endured this very, very late night, I yield the floor."
Democrats have revived the gun debate after 49 people were killed at a nightclub in Orlando, Florida early on Sunday, the worst such incident in modern history.
The fight pits strong proponents of the Second Amendment right to bear arms against those arguing for greater restrictions on the ability to obtain weapons.