Democrats and Republicans in the U.S. Senate struggled on Wednesday to agree on legislation to prevent future mass shootings a day after a gunman killed 19 children and two teachers at a Texas elementary school.

Democratic Senate Majority Leader Chuck Schumer urged collaboration but neither he, nor Democratic President Joe Biden in a televised speech on Tuesday, offered a specific approach.

"My Republican colleagues can work with us now. I know this is a slim prospect, very slim, all too slim," Schumer said in a floor speech. "It's their choice."

The Senate will hold a procedural vote on Thursday to launch debate on legislation to fight domestic terrorism that passed the Democratic-controlled House of Representatives after a mass shooting in Buffalo, New York, earlier this month.

Republicans Susan Collins and Pat Toomey said they had been in contact with Democratic Senator Chris Murphy about possible legislation to deny weapons to people deemed dangerous and to tighten background checks for gun purchasers.

Murphy, of Connecticut, where a gunman killed 26 children and educators at the Sandy Hook Elementary School in 2012, had implored his colleagues in a Senate speech on Tuesday to join together to battle gun violence.

"My interest in doing something to improve and expand our background system remains," said Toomey, who told reporters he has been in contact with Murphy. "The thing that would have the best chance would be the thing that's gotten Republican support before, which is expanding background checks."

Collins said the details of the Texas shooting appeared to suggest a role for "red flag" legislation that would employ the courts and medical profession to deny firearms to people deemed mentally ill.

"That is the kind of law that could have made a difference in this case, since ... it appears that he suffered from mental illness," the Republican moderate told reporters.

Democratic Senator Kyrsten Sinema said there was some chance of a deal on red flag laws: "There's some shared agreement on red flag, which I think might be a place to start conversations to actually get something done."

Senator Joe Manchin, one of the most conservative Senate Democrats, told reporters he would not agree to change Senate rules to allow Democrats to pass gun legislation on their own but held out hope for a bipartisan solution.

HUNDREDS OF DEATHS

Hundreds of people have died in mass shootings at schools, churches, stores and movie theaters over the years but Congress has failed to unite on legislation.

Republicans assert a right to bear arms protected by the Second Amendment of the U.S. Constitution. The political stalemate angers Democrats.

"It's fucking nuts to do nothing about this!" fumed Democratic Senator Mark Kelly, whose wife - former Arizona congresswoman Gabby Giffords - suffered a severe brain injury during an assassination attempt in 2011.

With the 100-seat Senate divided 50-50, Democrats would need support from at least 10 Republicans to meet the chamber's 60-vote threshold for most legislation.

Schumer has taken initial steps toward a possible vote on legislation to tighten background checks for gun purchasers.

His Republican counterpart, Republican Minority Leader Mitch McConnell, condemned the murderous actions of a "deranged" gunman and a "maniac" without addressing prospects for legislation.

Republicans became the target of gun violence themselves in 2017 when a gunman attacked lawmakers and colleagues at a baseball practice just outside Washington. Representative Steve Scalise was wounded in the attack.

Republican Senator Mike Rounds said that banning assault rifles or placing age restrictions on gun purchases would not have prevented the Texas shooting.

"Show us what would stop this from happening," Rounds said.

Schumer and other Democrats accused Republicans of being in the thrall of the gun industry and the National Rifle Association.

"One political party is owned by the gun industry, period," Democratic Senator Sherrod Brown told Reuters. "We've got to get a dozen Republicans and they don't show any sign of breaking with the NRA, ever."