Eliot Spitzer (Brendan McDermid/Reuters) Eliot Spitzer (Brendan McDermid/Reuters)

So much for second chances.

The losses by both Eliot Spitzer and Anthony Weiner in Tuesday's Democratic primary in New York brings to an end the supposed comeback season, in which at least three scandal-plagued politicians were taking a shot at redemption.

Their losses are bound to prompt plenty of after-the-fact analysis of whether this turns the conventional wisdom of the forgiving American voter on its head. We're supposed to be a sparing sort--people who, given the right amount of time and the right amount of contrite humility, are willing to absolve our leaders and move on. Do Spitzer and Weiner prove otherwise?

Well, making such comparisons is kind of pointless. Just like every unhappy family is unhappy in its own way, every unsavory political sex scandal is unsavory in its own way, too.

Mark Sanford may have been elected to the House of Representatives after an extramarital affair was exposed when he was governor, but he also ran in a heavily Republican district where conservatives were likely willing to hold their noses given that they saw him as the better candidate; he also later became engaged to the woman with whom he had the affair. David Vitter's phone number may have been connected with an escort service, but the timing of the news and a wave of conservative voters in the 2010 mid-terms helped with his re-election.

Indeed, Sanford and Vitter appear to be the exception rather than the rule: Plenty of disgraced politicians redeem themselves with respectable, or at least powerful, post-scandal careers. They go into academia. They hit the cable shows. They become lobbyists. But getting re-elected to public office after a sex scandal is still rather rare.

Maybe the notion that Americans are so willing to forgive and forget has gotten a little ahead of reality. Yes, we may be willing to re-embrace sports stars or actors who cheat on their wives after a little time and a heartfelt apology. And yes, we may be ready to listen to and even respect philandering politicians who move on to other careers. But as political scientist Alison Dagnes writes in the introduction to the book "Sex Scandals in American Politics," a politician is "famous for the leadership role he plays in government and for the promises he makes to the public in terms of good character and model behavior." Maybe--thank goodness--we still want to elect leaders who keep them both.

Jena McGregor is a columnist for On Leadership.

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