As Ben and Clay have been noting all week, Pete Coors and a pro-Schaffer 527 group backed by Bill Armstrong have been slinging around mud, er, negative advertising.

It appears that Armstrong was the first to start doing this, essentially accusing Coors of being not all that conservative. Coors responded by accusing Schaffer of being a career politician and of padding his resume. Resume-padding has been a problem for college football coaches of late, so maybe Coors is counting on that.

I'm sure that Schaffer will counter by saying that Coors accused him of voting to raise taxes, and Coors will talk about the Prime Minister of Canada, whose name he probably knows by now. (For any company, there's only room for one set of senior management. You know that ad where the Italian businessman comes back to find a phone he doesn't understand? How about coming back to find a Maple Leaf over your office door and a moving van outside? Guys, it was a leave of absence, not a pack-up-and-leave-in-my-absence.)

Also, while Schaffer has publicly disapproved of the ads, it's probably illegal for him to actually ask Armstrong to pull them. Independent 527 groups aren't allowed to coordinate with campaigns or parties, although, to be honest, they'd both have to be pinball wizards not to pick up the paper and get cues from each other.

The point is that nobody cares who said what first, and what pledges got signed about negative campaigning. As has been pointed out before, negative campaigning can help define differences. That's what these ads try to do. Armstrong really believes Schaffer is a more committed conservative; Coors really is running on his business background, as compared to a political background like Schaffer's.

The problem is that they both have the potential to be weapons in the general election. Coors essentially attacks Schaffer's honesty and character. But those charges are hard to transfer from primary to general. Should Armstrong be successful in getting conservatives to doubt Coors's credentials, it could leave a lasting impression that leaves conservatives more likely to sit at home on Election Day.

This is going to get worse over the next three weeks. But Armstrong's ads are probably more damaging to the party in the fall, and need to be pulled.

UPDATE: The Ft. Collins Coloradoan is reporting that Armstrong will not pull his ads. If Coors is really spending $250K a week on his, he's going to enter the general election with his main advantage - a warchest - pretty much neutralized. If Coors wins, will Armstrong keep his 527 up and running for the general?