But the weekend’s shootings — the shooter in Dayton used a modified military-style pistol, while the gunman in El Paso had an AK-47 rifle variant, according to authorities — are prompting many Democrats to rethink the issue.

“I think you can chart the rise of the modern anti-gun violence movement next to the diminishing number of Democrats who oppose an assault weapons ban,” Sen. Chris Murphy (D-Conn.) said. “As this movement has become an integral part of the Democratic coalition, it’s become a litmus test for Democrats coming into politics to support an assault weapons ban.”

The Democrats who oppose such restrictions, Murphy said, are an “expiring breed.”

Still, few believe an assault weapons ban is likely to advance in Washington anytime soon. President Trump said this week that there is “no political appetite” for such a ban, even as he publicly touts the possibility of expanded background checks despite private resistance from gun-rights advocates.