Dr. Mehmet Oz, who is running for Pennsylvania’s open Senate seat as a Republican, slammed primary opponent Kathy Barnette on Saturday for her history of posting Islamophobic tweets, Fox News reports.

If elected, Oz would be the first Muslim senator in United States history.

“We must stop interacting with them as if they r rational human beings. There is nothing rational about Islam,” Barnette tweeted in 2015. She also shared an article with the headline “Pedophilia is a Cornerstone of Islam.”

Oz, who has been endorsed by former President Donald Trump, said in an interview Saturday that he considers Barnette’s “Islamophobic” remarks to be “disqualifying.”

“This state was based on religious freedom. I’m proud as a Pennsylvanian to uphold those founding beliefs that every faith has its merits,” Oz said.

According to The New York Post, “Barnette has been outspent 358-to-1 on TV ads by her well-funded rivals,” Oz and former hedge fund CEO David McCormick, who have leveled scathing attacks at each other while leaving Barnette relatively unscathed.

In the past two weeks, Barnette — a military veteran and political commentator who has never held public office — has surged in the polls and is running neck-and-neck with Oz and McCormick ahead of Tuesday’s primary.