In his Sun-Times column last week, Rich Miller revisited Rep. Mark Kirk's various flip-flops since entering the race for U.S. Senate.  He noted that all this maneuvering has resulted in something that would have seemed unthinkable a few months ago: In recent weeks, the Chicago media has turned against the North Shore Republican:

Kirk's over the top, hyperbolic, error-riddled, extremely partisan fear tantrum [in response to the Thomson/Guantanamo proposal] finally tipped the media against him. Just about every significant newspaper in Illinois, including this one, which endorsed Kirk's re-election last year, mocked Kirk's meltdown and severely chastised him for needless and baseless fear-mongering. [...]

I think there's more at work here than just the usual rightward drift during a Republican primary. Kirk is clearly showing that he's far too susceptible to our disgusting and mindless national political wars, which endlessly play out on those idiotic cable TV "news" channels. And all this makes me question how Kirk would behave if he were elected next November.

Flip-flops in the midst of a campaign -- while they might boost a candidate's appeal among certain distinct groups -- always run the risk of eroding trust among the broader electorate.  I'm thinking about those large swaths of voters who observe campaigns from a non-ideological distance.  These citizens ultimately make their decisions based on their sense of a candidate's honesty and character -- not some policy checklist.

Up until now, Kirk has benefited from a McCain-esque depiction in the local media.  Editorial pages have regularly depicted him as a politician who purportedly puts principles above party and it's benefited him well.  But now that his glaring flip-flops are becoming part of the media narrative, he could be in real trouble.