A nasty little blogwar has broken out between Jesse of Pandagon and Lying in Ponds over the question of what "partisanship" actually means, and its relation to ideology. Jesse claims that the distinction is a false one, whereas Lying in Ponds argues that there's a strong difference.
I actually think he has a point on the difference between being ideological and partisan, because one can have a strong allegiance to a party and not be strongly ideological, and/or be strongly ideological but not attached to any particular party.
(Outside of the U.S. system of two ideologically based parties, it's actually quite common. Canadians have known about it for years; look at the NDP/Liberal or PC/Reform divide. Indeed, it's the close association between ideology and party that makes the Republicans so relatively unique.)
That being said, Lying in Ponds completely out to lunch on Paul Krugman; Krugman devastated the whole "partisanship" argument ages ago, driving a stake deep into the heart of LiP's methology that it has never truly recovered from. LiP's supposedly "quantitative" measurement of partisanship is entirely robbed of context, rendering it utterly useless, as (as Krugman noted) a supposed "partisan" could be an honest critic of a dishonest target. Partisanship isn't necessary for this and, because of this, is entirely unprovable by LiP's methodology. As the entire point of the exercise is to measure partisanship, it's rendered pointless, useless, and highly deceptive.
(Not surprising, as quantification of inherently qualitative media such as text is a tricky business at any time.)
So Jesse is wrong on this particular issue of definition, but the point remains that the entire Lying in Ponds exercise is just a sad joke. "Quantitatively", that'd even out... but in the qualitative real world, I'd say that Jesse comes out ahead.