As Pennsylvania’s U.S. Senate race heats up, incumbent Democrat Bob Casey features a Republican in his new ad, while the GOP candidate, U.S. Rep. Lou Barletta, plans to play to his base this week, hosting a rally with President Donald Trump.

Casey’s been a vocal opponent of Trump, joining an airport protest of his immigration policies and refusing to support his Supreme Court pick before the nominee was announced.

But Casey’s new campaign ad is an appeal to the center.

It features a western Pennsylvania couple, Kristin and Mike Wessell, who say they disagree on some things, but not on their U.S. senator.

“We admire how Bob Casey works with both sides,” Mike Wessell says in the ad. The couple then cites Casey’s support for health benefits for coal miners, bipartisan infrastructure plans, and even Trump’s call for tougher tariffs on Chinese goods.

Barletta press secretary David Jackson said in a statement that Casey “votes with Bernie Sanders and Elizabeth Warren over 90 percent of the time, defends dangerous sanctuary cities, will raise your taxes, and obstructs well-qualified nominees to the Supreme Court.”

“Casey cannot paper over his radical shift leftward,” Jackson added.

Casey spokesman Max Steele called Barletta “a lapdog for special interests” and said Casey works for the people of Pennsylvania.

“When Bob Casey agrees with the president, he’ll say so,” Steele said. “When he disagrees, you’ll know it.”

Casey is seeking his third Senate term.

Larry Sabato, a political scientist and founder of the University of Virginia’s Center for Politics, said in an interview Casey’s advantages in name recognition and money make the race an uphill fight for Barletta.

I asked if it’s smart for Barletta to embrace Trump so wholeheartedly.

“It may not work, but it’s the only approach he can take,” Sabato said. “His advantage in the race is that Donald Trump really cares whether he’s elected or not.”

“Trump endorses lots of people, but he clearly cares about the people who were early supporters and stuck with him through all his difficulties, and Barletta’s one of those,” he said. “So he’ll do what he can, and who knows? Maybe it will start a prairie fire closer to November.”

Trump won Pennsylvania in 2016 by 44,000 votes out of more than 6.1 million cast.

The Trump-Barletta rally is set for Thursday evening in Wilkes-Barre.

Find this report and others at the site of our partner, WHYY.