Sen. John Fetterman of Pennsylvania urged Americans on Sunday to suspend traditional politics and reflect on the gravity of the assassination attempt on former President Donald Trump, saying he doesn’t want to see more tragedies before November.

“We can’t assume that these kind of things can’t happen again,” Mr. Fetterman, a Democrat, told CNN’s “State of the Union.” “We have months ahead of us.”

Mr. Fetterman represents the state where the shooting unfolded.

Mr. Trump was struck on the right ear at the rally in Butler County, Pennsylvania, but survived and is reported by aides to be “fine.” He was walking unaided when he arrived in New Jersey early Sunday.

One rally attendee was killed and two others were critically injured, the Secret Service said.

“This was an incredibly dark day for Pennsylvania, but for our nation as well, too,” Mr. Fetterman said. “I can’t believe we’re actually in that place.”

Sen. Ron Johnson, Wisconsin Republican, said social media has stirred vitriol and turned Americans against each other. He told people to step away from their keyboards and engage in their communities.

“Find the areas of agreement,” Mr. Johnson told CNN. “America is something precious that needs to be preserved.”

Some rally attendees said they saw the shooter, identified as Thomas Matthew Crooks, 20, of Bethel Park, Pennsylvania, crawling on a roof near the venue. Agents killed the shooter.

President Biden rushed back to the White House from his home in Delaware late Saturday and was scheduled to receive a briefing on the incident early Sunday.

The House Oversight Committee asked Kimberly Cheatle, the director of the Secret Service, to testify at a July 22 hearing.

• Tom Howell Jr. can be reached at thowell@washingtontimes.com.