HARRISBURG — Public safety issues are shaping Pennsylvania’s U.S. Senate race and forcing Republican incumbent Pat Toomey and his Democratic challenger Katie McGinty to wade deeper into issues including terrorism and gun violence.

The campaign has been rapidly transformed by mass killings in Orlando and Nice, France, and the ambush killings of eight police officers in Dallas and Baton Rouge.

Responding to those crimes and showing unity with police have been priorities for both candidates.

“As the daughter of a police officer who walked the beat in Philadelphia, I know firsthand the sacrifices that police officers and their families make to protect us,” McGinty said in a statement about Sunday’s slaying of three officers in Baton Rouge. “Today, and every day, we all must stand together united in support of all those who do so much to keep us safe.”

She also said making it harder for suspected terrorists to get assault weapons would improve safety and protect police. Efforts in the U.S. Senate to tighten gun-buying restrictions on suspected terrorists failed last month, largely along partisan lines.

Toomey called Baton Rouge a “dark chapter in anti-police violence that seems to be spreading across our country.”

“It’s long past time for us to come together and support law enforcement who face many risks and sacrifice so much to keep us safe,” Toomey said in a campaign statement. “We cannot allow these acts of violence to become the new normal, and we cannot turn a blind eye to some of the anti-police rhetoric that is fueling it.”

An Associated Press-GfK poll this month found that the threat of terrorism and stemming illegal immigration are top concerns for most voters, but they’re highly divided on how to do it.

A new TV ad by Toomey criticizes McGinty for backing President Barack Obama’s Iran nuclear deal and claims she supports closing Guantanamo Bay and moving “terrorists” to U.S. prisons and allowing immigrant “sanctuary cities” such as Philadelphia.

McGinty supports the Iran nuclear deal but said Toomey’s Guantanamo Bay claim is “full of baloney.”

“I never endorsed bringing prisoners from Guantanamo Bay to the United States,” McGinty said in a statement. She said there are real questions about whether released prisoners are re-engaging in battle and, until those questions are answered, she will not embrace Obama’s plan to close the prison.

McGinty also recently urged Philadelphia’s cooperation with federal immigration authorities and blamed Congress and Toomey for failing to fix the nation’s immigration system. Toomey voted against bipartisan immigration legislation that passed the Senate in 2013.

In his time in the Senate, Toomey has waded into some public safety issues. He crossed party lines in 2013 to support a gun control bill, and earlier this year he introduced legislation to reverse Obama’s order ending federal transfers of some military combat-style gear to police agencies. A McGinty campaign spokesman called that a “stunt bill.”

Still, the violence of this summer has overshadowed the candidates’ foundational themes.

Toomey ran in 2010 on his reputation as a strict fiscal conservative, and kicked off this campaign by touting his work across the aisle, such as on eliminating sugar and ethanol subsidies. Meanwhile, McGinty began her campaign by attacking Toomey as an enemy of the middle class and women’s rights.