The candidates for Pennsylvania’s open U.S. Senate seat — Republican Mehmet Oz and Democrat John Fetterman — meet tonight for their only debate. The outcome has been framed as a referendum on Mr. Fetterman’s health following a stroke, which offers a grim prognosis for Dr. Oz.

The stroke has left Mr. Fetterman with difficulty understanding speech; so, he will have someone transcribing what the moderators and his opponent say, projecting them onto a monitor visible to both candidates. Expect even better results than the transcription software that the Democrat has been using in interviews.

On October 17, I wrote a column asking, “Will Dr. Oz Stumble Into the Pit of Lowered Expectations?” That was because the Fetterman team had been dropping the bar until it lay on the ground. It’s a strategy they’ve continued to execute unchallenged.

Just yesterday, the Philadelphia Inquirer ran an article under the headline, “‘It’s … Going to Be a Challenge’: Fetterman Downplays Expectations for Pa. Senate Debate with Oz.” In an interview with the paper, Mr. Fetterman said he expected to miss words, “But we’ve always maintained that we’re going to participate.” 

Note that this is not a promise of victory, a boast of rhetorical prowess, or even a claim that he’ll be competitive in a robust exchange of ideas. Mr. Fetterman can “participate” just by standing on the stage at Harrisburg for the full 60 minutes.

Unlike President George W. Bush’s team describing Vice President Gore as “the best debater in modern American politics,” Republicans have done nothing to raise expectations for their opponent, which would have been easily done by focusing on his political resume versus the newcomer.

So, viewers have been infused with sympathy for Mr. Fetterman before the opening statements, seeing him as a brave, even heroic figure, striving to overcome a disability to meet his opponent. That he’s done so only after being forced — and after half a million votes have been cast — won’t enter the average voter’s mind unless Dr. Oz puts it there.

Even if Dr. Oz makes the point, you can count on Democrats to accuse him of picking on an infirm opponent. This would undercut the Republican’s persona — that of a caring doctor dedicated to healing — as would any similar angle of attack. Don’t be surprised if Mr. Fetterman challenges the doctor to apologize for all criticism related to the stroke.

Mr. Fetterman has already made common cause with the millions who use closed captioning. I’d be surprised if he doesn’t presume to speak for all victims of neurological problems, much as President Biden blames a childhood stutter to excuse his estranged relationship with the spoken word.

Dr. Oz’s prowess as a TV personality will also be undercut by all eyes being on his opponent, waiting for him to crumble. Furthermore, Dr. Oz’s polished manner of speech will enable the person transcribing him to execute the job with high accuracy.

In politics, as in sports, fans don’t shed tears when a star player on the other team suffers injury, but only 39 percent of Pennsylvanians registered to vote are Republicans who can be counted on to root against Mr. Fetterman’s chances. The 46 percent of registered Democrats will be rooting for their guy, and the 15 percent of unaffiliated voters will just want to see a good game.

In post-debate analysis, the press will lean toward Mr. Fetterman, as most are Democratic and the storyline of an underdog overcoming the odds will prove too compelling to resist. Republicans in general are reported by the punditry as tying or losing debates — and even if Dr. Oz wins, he has only beaten up on someone running at half strength.

As President Nixon learned in his debate with President Kennedy in 1960, television is a visual medium. Those listening on the radio believed Nixon won on the issues, but viewers said Kennedy’s style prevailed. Tonight, there will be few voters listening and millions watching — all of which bodes well for Mr. Fetterman who, by showing up, is set to emerge victorious.