Washington (AFP) - Key US lawmakers expressed guarded optimism Sunday that the shocking school shooting in Texas might lead to at least small steps against gun violence.

"There are more Republicans interested in talking about finding a path forward this time than I have seen since Sandy Hook," Democratic Senator Chris Murphy said on ABC, referring to the 2012 school shooting in his home state of Connecticut that claimed 26 lives.

Since the shooting Tuesday in the town of Uvalde, Texas left 19 children and two teachers dead, Murphy has been a leader in talks with Republicans -- who have long resisted gun-control measures -- about potential steps.

Dick Durbin, the number two Democrat in the Senate, said Sunday that compromise would not come easily, but that after Uvalde, he sensed "a different feeling among my colleagues."

"The real challenge is whether the Republicans will step forward and show courage, political courage, in a very tough situation," he told CNN.

But, he added, "There will be some."

One moderate House Republican, Adam Kinzinger, told CNN that Uvalde might have opened him up to greater gun control measures.

Kinzinger, a military veteran, said he had opposed the idea of a ban on assault-style weapons until "fairly recently."

But, he added, "I think I'm open to a ban now," or at least to imposing training or certification requirements on potential buyers.

"We have to be coming to the table with ways to mitigate 18-year-olds buying these guns and walking into schools," he said. "My side's not doing that."

Opposition to gun control runs deep among Republicans and some Democrats representing rural states.

In the wake of the Uvalde shooting, several Republican lawmakers have advocated improved school security or additional mental health support.

Durbin acknowledged the difficulty of achieving real reform in a country where guns outnumber people.

"The AR-15 that was used by this individual in Uvalde, there are now 20 million of those owned by Americans across the nation, just to put it in perspective," he said.

"So we have got to be realistic about what we can achieve."