Republican presidential candidate Newt Gingrich could stand to benefit in the polls from Herman Cain’s reassessment of his own campaign. (Erik Kellar/AP)

Yes, the same man who had two extramarital affairs—including one with his current wife that was going on about the time he was trying to impeach Bill Clinton for his relationship with Monica Lewinsky—is apparently okay to GOP voters, while Cain, increasingly, is not. Of course, there have also been sexual harassment allegations swirling around the Cain camp for weeks. But it wasn’t until the news of the affair was made public that talk began of Cain possibly ending his campaign. (Cain has denied both the claims of sexual harassment and that he had an affair with Ginger White; he also appears to be reassessing what “reassessing” his campaign really means.)

There are many reasons why voters might shun one and embrace the other. The anti-Romney sentiment is likely so strong that GOP voters will simply overlook anything. The sexual harassment allegations may have taken too much of a toll. The flavor-of-the-month mentality of the GOP campaign may just be cycling its way to Gingrich. And then there is Gingrich’s long history in Washington, which is apparently making him increasingly attractive to older voters willing to look past his personal foibles, despite the conventional wisdom that D.C. insiders are out of favor in the Republican party.

But most likely, it’s that when it comes to their current and would-be political leaders, American voters who have long been cited for their ability to forgive also have a very good capacity to simply forget. Not only has Gingrich had two extramarital affairs; he was the first Speaker of the House to be disciplined for ethical wrongdoing. He resigned from the Speaker position in 1998 when faced with a rebellion from members of his own party. And Gingrich’s supporters have conveniently forgotten that their candidate pushed a federal health-insurance mandate in the early 1990s as an alternative to Hillary Clinton’s proposals.

This forgive-and-forget mentality is especially the case for a presidential candidate who has not held public office since 1998. He’s now married to the congressional aide he had the last affair with, and has re-established his conservative bona fides, at least to some, through his successful moneymaking ventures. Although some recent embarrassments could haunt him in this campaign, such as the $1.6 to $1.8 million in fees he reportedly received from the controversial mortgage firm Freddie Mac, so much time has elapsed since he was in office that the shock voters might have felt about the Speaker of the House’s ethical or extramarital transgressions 15 years ago have been papered over by other recent scandals.

Voters’ collective consciousness, fueled by the latest media firestorm, seems already to have forgotten about Gingrich’s Tiffany expense accounts and his luxury Greek cruise in the middle of a presidential campaign. So it’s not surprising that decade-old extramarital affairs, whatever the reason, have been forgotten as well. In today’s world, political leaders can count on their images being shaped not just by what they’ve achieved, but by when the most recent scandal comes along to make their own transgressions look relatively benign in context. As the historian candidate should appreciate, political pasts—like history—are being constantly remade.

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