LAS VEGAS — Democratic presidential candidates reiterated their call for gun control Wednesday and urged Americans to keep up the fight for change, sidestepping the issue of impeachment in Washington and whether it will divert lawmakers.

At a gun policy forum in Nevada, Cory Booker said the National Rifle Association and the corporate gun lobby are not the only forces stopping progress on gun control.

“Change never comes from Washington. It comes to Washington by Americans that demand it,” the New Jersey senator said. He added later that “Every one of us in America, right now, by doing nothing, we are implicated in this. …. We all have to take responsibility.”

The forum — located about 2 miles from the Las Vegas Strip, the site of the deadliest mass shooting in modern American history — was held amid an effort to keep gun violence front and center of the debate and gave 2020 presidential candidates a chance to showcase their plans to combat the epidemic. Negotiations between President Donald Trump’s administration and lawmakers have halted over background checks legislation passed by the Democratic-controlled House, an effort that faced long odds even before the impeachment inquiry began.

“This president has gotten nothing done about much of anything,” California Sen. Kamala Harris said Wednesday, adding that Trump will use impeachment as an excuse to avoid action.

Former Vice President Joe Biden made a similar prognosis, saying, “Nothing is going to change until we get this guy out of office.”

They were among nine White House hopefuls to speak at the forum Wednesday, two years to the day after a man rained gunfire from the window of a high-rise hotel onto a country music festival below, killing 58 people. The forum was hosted by MSNBC, March for Our Lives and Giffords, the advocacy organization set up by former Arizona congresswoman Gabby Giffords, who was shot and gravely wounded during a constituent meeting in 2011 in Tucson.

Giffords opened the event with brief remarks calling for Democrats, Republicans and independents to come together and fight for change.

“Stopping gun violence takes courage. The courage to do what’s right. The courage of new ideas,” Giffords said.

In addition to Booker, Harris and Biden, the other candidates who spoke were South Bend, Indiana, Mayor Pete Buttigieg; former Obama Housing Secretary Julián Castro; Minnesota Sen. Amy Klobuchar; former Texas Rep. Beto O’Rourke; Massachusetts Sen. Elizabeth Warren; and businessman Andrew Yang.

Vermont Sen. Bernie Sanders was expected to attend, but he ended up undergoing a heart procedure for a blocked artery. His campaign said he was canceling appearances “until further notice.”