Pennsylvania Republican Dave McCormick is set to take the stage at the Republican National Convention Tuesday night along with other Senate candidates. But his speech might sound a little different. 

McCormick has updated his planned remarks to address Saturday’s attempted assassination of former President Donald Trump, according to a source familiar with his speech. Unlike the other Senate hopefuls, McCormick witnessed the shooting firsthand. 

Just three days ago, McCormick was seated in the front row of Trump’s rally in Butler, Pennsylvania, and took cover as the gunman opened fire.

“Lots of energy and lots of positive noise and then all of a sudden, just shattered with these rifle shots,” McCormick told NBC News Saturday night. “And it was just sort of — people were in disbelief. It was very chaotic and very confusing for quite some time.” 

McCormick is in a hotly contested race against Democratic Sen. Bob Casey in a state that is key to both the race for the White House and the battle for the Senate. And while it’s yet not clear if or how Saturday’s shooting will affect elections this fall, any effects may be felt particularly strongly in Pennsylvania.

“I think because this incident occurred in Pennsylvania, you would imagine it’s going to have more of an impact in Pennsylvania than other places,” said Mike Barley, a former executive director of the state GOP. 

The shooting did have a temporary impact on the Senate race: Casey’s campaign began working with local TV stations on Saturday evening to temporarily take down its ads. Campaign spokesperson Maddy McDaniel said in a statement that the ads will resume “in the days ahead to educate Pennsylvanians on Senator Casey’s record, his opponent’s record and the stakes of this Senate race.”

On Monday morning, McCormick also called on Casey to agree to “suspend negative advertising.” (McCormick did not call on outside groups, which cannot coordinate with campaigns but launch many of the negative spots, to cease their attacks as well.)

Saturday’s shooting could also raise more immediate concerns about security at upcoming campaign events. 

”Safety needs to be top of mind,” said GOP state Rep. Stephenie Scialabba, who was next to McCormick on Saturday when the gunman opened fire.

“We’re all standing there, having these discussions about the future of the country. And next thing you know, we’re making eye contact under folding metal chairs, counting the shots and trying to determine where they’re coming from,” she recalled.

Scialabba said McCormick helped shield her and told her, “I got you,” confirming her account to the Butler Eagle. 

“It’s like his combat training kicked in and he was able to get us all out of there,” Scialabba said, referring to McCormick’s service as a former Army officer and veteran of the Gulf War. 

Scialabba said she is concerned about attending future campaign events, but she plans to go anyway “out of pure defiance.” She echoed other elected leaders and called for “extra thought” into language used in campaigning “to tone down this rhetoric.”

Both Casey and McCormick have also called for lowering the temperature. 

“We have consequential differences; we should debate them robustly,” McCormick wrote in a Wall Street Journal op-ed Sunday. “The left and right have vastly different visions, and both fear the consequences of losing. So let’s have that conflict—but let’s commit to keep it inside the context of elections, civil debate and policymaking.”

Casey told CNN’s State of the Union on Sunday, “We all have a role to play … both as citizens and as elected officials. What we should be categorically condemning is violence of all kinds, political violence or otherwise.” 

It remains to be seen if cooling down rhetoric is even possible in today’s ever-warming political climate — especially in a battleground state as critical as Pennsylvania. 

Some Pennsylvania political operatives were cautiously optimistic.

“Sen. Casey has always shown that he’s run campaigns based on substance, not style. And look, McCormick, in all honesty, strikes me the same way,” said Pennsylvania Democratic strategist Mike Mikus, who is not working with Casey. “This race was never going to be an over-the-top battle royale. It was always going to be based on differences both on policy and background.” 

Barley, the former state party leader who is not working with McCormick, also said a more positive campaign is possible “because of the unique nature of the two people.” 

“I think they’re both generally gentlemen. And they like to campaign that way,” Barley said — though he added that the candidates cannot control the largely negative ads that come from outside groups. 

Pennsylvania GOP strategist Vince Galko, who is not involved in the Senate race, said there could be “more civility, more issue-based campaigning” in the short term. But Galko noted McCormick will also have to make his case against the incumbent. 

McCormick has continued to draw a contrast with Casey, telling CNBC on Monday that his message to voters is: “If you think the status quo is OK, if you think we’re on a good path, then you should vote for my opponent. Sen. Casey, he’s been there a long time. He’s voted with President Biden 98% of the time. If you think we need to make really significant changes on the border on economic policy, on criminal justice, on America’s role in the world, on energy policy — then, then pick me.”

Casey and his allies, meanwhile, have also been working to define McCormick, highlighting McCormick’s business record and his Connecticut residence.

Aside from some potentially less hard-edged messaging, it’s not yet clear if it could have a broader impact on the Senate race. 

McCormick faces a tough race against Casey, the son of a former governor who was first elected to the Senate in 2006. While Republicans argue the race will tighten as McCormick becomes better known, Casey has performed better than President Joe Biden in recent polling. 

A Pennsylvania survey from New York Times/Siena College, conducted last week, prior to the shooting, and released Monday, finds Casey at 50%, leading McCormick by 11 points among registered voters and 8 points among likely voters. Casey’s leads are outside the survey’s margins of error for both groups. The survey found Trump leading Biden by 3 points among both groups of Pennsylvania voters. 

Casey has historically fared well in Western Pennsylvania, even as Republicans have made inroads in the Trump era among blue-collar voters in the industrial areas surrounding Pittsburgh. 

That part of the state is also where Saturday’s shooting took place. 

“That’s the most important place in the whole race,” GOP strategist Brad Todd, who is working with McCormick’s campaign, said of Western Pennsylvania.

“There will be a whole lot of people in Butler and the surrounding counties who know people who were there, who’ve heard firsthand accounts,” Todd said, later adding, “I don’t know if that results in more engagement, if it results in more people paying attention, if it’s more enthusiasm.”

“I don’t know how it will change,” Todd added. “But I have to believe it will change.”