Pennsylvania Democratic Senate candidate John Fetterman is out with a new ad mocking his GOP rival Mehmet Oz and comparing the celebrity surgeon to a quack doctor character from “The Simpsons.”

“Before there was Dr. Oz, there was Dr. Nick,” Fetterman wrote in a tweet Monday, referring to the recurring character from the long-running animated sitcom. “They say the Simpsons always predict the future – and once again, they nailed it.”

The campaign ad includes clips of the cartoon doctor selling miracle cures alongside clips from “The Dr. Oz Show” in which Oz pitches various treatments. The ad ends by parodying the Republican’s campaign logo, replacing “Dr. Oz” with “Dr. Nick.”

The retired cardiothoracic surgeon rose to television prominence as a guest health expert on “The Oprah Winfrey Show” before snagging his own program. He ended “The Dr. Oz Show” in January after 13 seasons in order to launch his Senate bid.  

Fetterman and Oz have traded hits in a tense race to fill the seat being vacated by retiring Sen. Pat Toomey (R). 

Recent polling has put Fetterman, Pennsylvania’s lieutenant governor, ahead of Oz by a small margin, but indicate his lead may be shrinking as the midterm elections approach. 

The Hill has reached out to Oz’s campaign for comment.