Former Rep. Beto O’Rourke said Saturday night that President Donald Trump's rhetoric on race played a role in the mass shooting that killed at least 20 people in El Paso.

With Congress recessed for August, any gun-control fight is likely to play out between Democratic presidential contenders and the White House. Gun control has already been a prominent theme in the Democratic presidential primary, where candidates broadly agree on legislation such as universal background checks. Some candidates have gone farther than others with plans to curb the flow of guns in the U.S. if they were president, such as a vow by Sen. Kamala Harris of California to take executive action within 100 days and a proposal by Sen. Cory Booker of New Jersey to set tougher standards for firearm ownership.