If you’re wondering why the administrators at Daily Kos are suddenly hitting the delete button for (some) posts that try to spread ugly rumors about Sarah Palin’s family, here’s your answer:

The McCain campaign was outraged by the blog rumors. “There’s no doubt that liberal blogs such as one called www.barackoblogger.com and some in the mainstream media were pushing a false story about Gov. Palin’s most recent pregnancy with fervor,” said senior McCain adviser Nicolle Wallace.

A senior McCain official said its camp had no evidence that the campaign of Democrat Barack Obama was pushing the story, but said the blog rumors circulating on websites that appeared to support Obama had the effect of being “a real anchor around the Democratic ticket.”

Speaking to reporters in Monroe, Michigan, Obama said he was offended by the McCain aide’s statement and that he considered people’s families off-limits.“We don’t go after people’s families. We don’t get them involved in the politics. It’s not appropriate and it’s not relevant. Our people were not involved in any way in this and they will not be. And if I ever thought there was somebody in my campaign that was involved in something like that, they’d be fired,” Obama said.

Obama also said: “This shouldn’t be part of our politics. It has no relevance to Gov. Palin’s performance as a governor or potential performance as a vice president. So I would strongly urge people to back off these kinds of stories.”

Kudos to Obama for saying the right things, at least. But the Democratic Party in general has been tacitly, sneakily encouraging this kind of behavior for years; it isn’t surprising to see the Nutroots finally rearing up and biting the DNC on its posterior.