A Double Standard on Political Affairs

This week, former Democratic presidential candidate John Edwards has been (rightly) criticized after finally admitting to having an affair with a woman who worked on his campaign. While much of the coverage on this story focuses on the possibility of an illicit love child born earlier this year, I find marked inconsistency from right-wing blogs (and to some extent, the mainstream media) in coverage on this event. Let us not forget that John McCain, too, cheated on his wife, divorcing her after she was in a car wreck and later marrying a woman 20 years his junior.
I'm not saying that either of these men can be defended for what he'd done. Cheating in any circumstance is completely wrong, but it is even worse when your spouse suffers from some sort of affliction (Elizabeth Edwards - cancer; Carol McCain- disfigurement from car crash). The fact that McCain ended up marrying his mistress does not change the fact that he cheated on the person he was married to at the time. The fact that he's been married to her ever since is not an ablution to the stain of the original sin.
Both of these men cheated on their wives. Time notwithstanding, one is getting off lightly, and another is being strung up on the front pages of every major publication in the world. Now tell me: both crimes being equal, how is that a balanced response?