WASHINGTON — More than 24 hours after seizing control of the House floor, Democratic lawmakers Thursday ended a noisy, unusual sit-in after being unable to push Speaker Paul Ryan to call a vote on legislation to curb gun sales.

Democrats sat on the chamber floor, spoke passionately about victims of gun violence and sang “God Bless America” into the wee hours outside the Capitol. But by Thursday morning they were protesting to an almost empty chamber after Republicans recessed for the long Independence Day holiday week.

Outside on the Capitol steps, Democratic members were greeted as they left with shouts of “We're with you!” from a crowd that had gathered overnight and into the morning.

Attention shifted to the Senate, where momentum was building to show Congress was willing to do something — even a modest bill — in response to the mass shooting in Orlando, Fla. But passing the legislation remains a long shot.

Most Republicans, who have control of Congress, oppose the measures to prevent terrorism suspects from buying guns or expand background checks for purchases, saying such provisions might infringe on the constitutional rights of innocent people.

Even though a Senate compromise to prevent a narrow group of terrorism suspects on the no-fly list from buying firearms won bipartisan support Thursday — eight Republican senators joined all Democrats in a test vote — its future remains in doubt.

Ryan insisted the sit-in was nothing more than a “publicity stunt.”

“They're staging protests, they're trying to get on TV, they're sending out fundraising solicitations like this one,” the speaker from Wisconsin said of Democrats, holding up copies of fundraising emails.

“If this is not a political stunt, then why are they trying to raise money off of this — off of a tragedy?”

“They know this isn't going anywhere,” Ryan said. “Our focus needs to be on confronting radical extremism. Terrorism is the issue.”

While several Senate Republicans in tough re-election battles this fall are willing to consider new gun restrictions, rallying enough of them to reach the 60-vote threshold to advance the bill is not likely.

Thursday's Senate test vote, with 52 senators refusing Majority Leader Mitch McConnell's motion to shelve the compromise, offered a high-water mark for GOP support but still fell short of the 60 votes that would be eventually needed for full passage.

“Surely, on an issue of this importance, we should be able to come together and work for common sense solutions,” said Republican Sen. Susan Collins of Maine, who led the bipartisan effort. It remains unclear whether the legislation will be brought up again after the holiday break.

Advocates of stricter gun control laws believe public patience is nearing a tipping point in the aftermath of Orlando, as well as the shootings at a holiday party in San Bernardino, Calif., a church in Charleston, S.C., and an elementary school in Newtown, Conn.

“The American people are with us,” Rep. John Lewis, D-Ga., the legendary civil rights leader, told his colleagues. “Be optimistic.”

The protest that started about 11:30 a.m. on Wednesday continued overnight as crowds gathered at the Capitol, cheering on Democrats and at times breaking into patriotic song.

Until they left Thursday afternoon, Democrats continued to hold the floor even after Republicans departed for the holiday break.

“What are we going to do, just say it's OK for people to get slaughtered every six weeks?” said Rep. Nancy Pelosi of California, the Democratic leader.

Democratic lawmakers vowed to continue pushing for votes when the House returns July 5.

“So many of my constituents wrote to me, contacted me over the past 24 hours,” said Rep. Frank Pallone, D-N.J., reading a note from one who urged lawmakers to keep protesting until they get a vote.

“I promise you ... that is what we will do,” the congressman said.

lmascaro@tribune.com