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A Democratic senator ended a nearly 15-hour-long filibuster on the Senate floor early Thursday, part of an effort to force a vote on gun control legislation following Sunday's terror attack in Orlando.

Sen. Chris Murphy, D-Conn., yielded the floor at 2:11 a.m., 14 hours and 50 minutes after he began speaking. Murphy kept up his filibuster to a mostly empty chamber, save for 38 Democratic senators who joined him and made their own speeches throughout the day. Two Republican senators, Ben Sasse of Nebraska and Pat Toomey of Pennsylvania, also made remarks.

Democrats were seeking a vote on two amendments to an underlying spending bill. One, proposed by Murphy, would expand background checks. The other, proposed by Sen. Dianne Feinstein, D-Calif., would let the government bar sales of guns and explosives to people it suspects of being terrorists.

Republicans argue that Feinstein's bill denies due process to people who may be on the terror list erroneously and are trying to exercise their constitutional right to gun ownership.

Near the end of the filibuster, Murphy said that Senate leaders had promised "a path forward" for floor votes on the legislation, but did not elaborate further.

As he began to speak Wednesday morning, Murphy said he would remain on the Senate floor "until we get some signal, some sign that we can come together," and evoked the Newtown school shooting in his state in 2012.

"For those of us that represent Connecticut, the failure of this body to do anything, anything at all in the face of that continued slaughter isn't just painful to us, it's unconscionable," Murphy said.

Separately Wednesday, the National Rifle Association reiterated its support for a bill from Sen. John Cornyn, R-Texas, that would let the government delay firearms sales to suspected terrorists for up to 72 hours. Prosecutors would have to persuade a judge to block the transaction permanently, a bar Democrats and gun control activists say is too high.

The Orlando shooter, Omar Mateen, was added to a government watch list of individuals known or suspected of being involved in terrorist activities in 2013, when he was investigated for inflammatory statements to co-workers. But he was pulled from that database when that investigation was closed 10 months later.

Efforts to compromise between the Cornyn and Feinstein bills collapsed within hours of surfacing in the Senate Wednesday, underscoring the extreme difficulty of resolving the divisive issue five months to the election.

Meanwhile, Everytown for Gun Safety, a gun control group backed by former New York Mayor Michael Bloomberg, said it was working on a compromise with Toomey.

By the end of the day Wednesday, Toomey, who is facing a tough re-election race this fall, had introduced legislation that would direct the attorney general to create a new list of suspected terrorists who could be barred from buying weapons. But Democrats immediately rejected that idea, saying it would create too much of a backlog.

Fox News' Chad Pergram and the Associated Press contributed to this report.