Julian Zelizer is a history and public affairs professor at Princeton University and the editor of "The Presidency of Barack Obama: A First Historical Assessment." He's also the co-host of the "Politics & Polls" podcast. Follow him on Twitter: @julianzelizer. The opinions expressed in this commentary are his own.

(CNN) Republicans should be worried about Anderson Cooper's "60 Minutes" interview with the porn actress Stephanie Clifford, who performs as Stormy Daniels, coming days after the CNN anchor interviewed former Playboy model Karen McDougal.

As they listen to the women recount stories of relationships they say they had with the married Donald Trump (affairs which he denies), they may not be able to avoid thinking about what it will mean at the ballot box in November.

In special elections, Republicans have been struggling to retain vacant seats even in solidly red districts, as the Trump effect starts to take a toll. And the potential for women's votes to determine the outcome of the midterms is immense.

There are many parts of the Daniels story that probably won't add up to anything more than salacious and disturbing tales from Trump's private life. The details of his alleged infidelity to Melania and his sexual peccadilloes, as well as the images that might be on the mystery CD or DVD tweeted about by attorney Michael Avenatti, are not likely to move the political needle given that most of the public already has a pretty good sense of who the President is as a person.

If these interviews are really eye-opening to you, then you probably have not been paying attention. Even the evangelical voters who have decided to set aside their principles and give Trump a "mulligan" because of his right-leaning nominations for judgeships never believed that President Trump was an angel.

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