Las Vegas (CNN) Joe Biden is focusing his campaign on gun violence ahead of Saturday's Nevada caucuses, criticizing Bernie Sanders by name and accusing "cowards" in Congress of being scared into inaction by the National Rifle Association.

The former vice president delivered one of his most focused, forceful speeches of the 2020 race Thursday in Las Vegas -- the site of the deadliest mass shooting in American history , where a gunman killed 58 concertgoers in 2017.

Standing behind Biden were family members of gun violence victims and gun control advocates -- many of whom were members of Moms Demand Action, the grassroots arm of a group largely funded by Michael Bloomberg . The walls were plastered with new signs that read "Beat the NRA with Biden." He was introduced by a woman whose 4-year-old daughter had been killed by a stray bullet, and Democratic Rep. Steven Horsford of Nevada, whose father was killed when Horsford was 19.

Biden began by declaring it a beautiful morning and noting that the sun was shining. But, he said, by the end of the day, 100 Americans would be dead because of gun violence -- "another normal day in America."

"Normal has become a living nightmare," he said.

Biden at one point criticized Sanders, the Democratic presidential front-runner, by name for his votes against gun control measures in the 1990s, including the Brady Act, which mandated federal background checks and a waiting period for some handgun purchases.

Afterward, he acknowledged that Sanders now supports gun control measures.

"I do think he's changed his views. I'm happy for that," Biden said.

The increased focus on gun violence marks an important turn in Biden's message after weak finishes in the Iowa caucuses and New Hampshire primary.

For most of his campaign Biden's message has looked backward at his record in former President Barack Obama's administration, and focused on his perceived electability -- a factor outside the former vice president's control.

But on gun violence, Biden connected his own record that predates Obama to a forward-looking vision for his own administration, as the presidential race shifts to states that have been the sites of mass shootings -- including the 2015 Charleston church massacre in South Carolina and the August 2019 shooting in El Paso, Texas , one of 14 states that votes on Super Tuesday.

Biden was the only candidate to bring up gun violence in Wednesday night's debate in Nevada. He has focused television advertisements on the issue. And at a Nevada caucus kick-off dinner, Biden pledged that he would "not rest" on the issue until his "last breath."

The former vice president on Thursday focused on requiring universal background checks for gun purchases, banning the sale of high-capacity magazines and assault-style rifles, and repealing civil liability protections for gun manufacturers.

He called those protections "flat-out immoral." Pounding on his podium and shouting, Biden said that in the United States, there have been "150,000 people murdered since 2005."

"You know, any one of you and the people behind me should be able to walk into a court of law and demand that gun manufacturers with their enormous profits be held accountable for the carnage they're responsible for inflicting on society," Biden said. "I promise you, if I'm our next president, they're going to be held accountable, because I'm coming after them."

He said those civil liability protections are unique to the gun industry -- and compared them in personal terms to heavily regulated industries such as tobacco and oil companies, auto manufacturers, pharmaceutical drug and chemical-makers.

"Why are guns different? Because of cowardice," he said. "Because of cowards that are afraid to take on the special interests because they're so damn powerful."

"I will not rest until we beat these guys," Biden said.