If you want to see what the left thinks of establishment Republicans (like Utah's Bob Bennett) losing in the primaries, this sneering post at Crooks and Liars is a good place to start.
Bennett's unforgivable Senate sins were, according to local party hacks officials, daring to consider any form of health care reform, his TARP vote and other ideological votes around constitutional issues like the flag burning amendment. Despite Mitt Romney's endorsement, party purists coalesced around the money and the tea party take-no-prisoners doctrine, respectively.
It's odd to me that the same people fainting over "hope" and "change" are deriding anyone on the right who actually means it. Instead, what we get is complaints about the "far right" taking over the party. A tip for the nutroots: when you are holding up Gerald Ford and George H.W. Bush as the Republicans you like, you aren't going to win many friends among conservatives.
Oh, I know. The nutroots aren't really interested in the GOP being affective in any sense (unless it's in helping Democrats pass their agenda). But still, the concern trolls on the left need to do a little more work on their act.