I'm back from an interesting Western Political Science Association conference, so here's a political sciencey type of post, although I think it will be of general interest. My panel was nice, but it did get me thinking. The most interesting paper on my panel (unless I count my own, but that's cheating) was an attempt by Ray LaRaja and David Wiltse to figure out whether campaign donors were (at least partially) responsible for the rise of party polarization, at least in Congress. The paper is still a work in progress, so I won't comment much on it other than to say that in my view it's an important question and they have a good chance to shed some light on the subject.
I also realized that at this late date, we still don't know how much money comes from partisan sources. Let me explain. There are two ways of thinking about the sources of campaign financing. One is to look at the formal sources of money flowing to candidates, of which there are four in Congressional campaigns: individuals, PACs, formal party organizations, and the candidates themselves. Those categories can be useful in some ways and have the (very real) virtue of being easy to access, but they are not, unfortunately, useful for answering some very important questions.
That's because what we really want to know, at least sometimes, is a very different set of categories. What we often want to know is whether money spent in an election comes from parties, interest groups, or from individuals particularly interested in and loyal to a particular candidate. The problem is that the first set of categories is not, in fact, a good proxy for questions we have about the second set of categories.
I should explain. PACs might be interest groups -- but they might be party-aligned groups, groups that are really best thought of as portions of a broader party network (what I call the expanded party). Individuals might be unconnected individuals, but they might be giving in response to requests from an interest group, or they might be partisans who have no particular interest in any particular candidate, but give in order to help the party control Congress. Of course, they also may be friends or supporters of the candidate.
From the point of view of most of the questions we ask about Congress (and the same logic applies to the presidency, or other offices for that matter) it's that second set of categories that's really most interesting. Usually, when we ask how much money a candidate received from "the party," we don't really care whether the money came from (say) the DCCC, or from a party-aligned interest group, or from a bunch of individuals who were referred to that candidate by a left-leaning web site. We want to know whether the candidate was backed by the Democrats or not.
Unfortunately, this is a whole lot harder to get a handle on than are the FEC-created groupings. As far as I know, the only work on this are some studies in progress by Casey Dominguez. The general idea is that an interest group or an individual who only gives to one party, but gives to many candidates (and perhaps to formal party organizations) from that party, should be classified as a party donor. On the other hand, an individual who mirrors the donations of an interest group should probably be classified as part of that group (the excellent Open Secrets does something that is a bit different, but also promising: they match occupation with industry).
The question that La Raja and Wiltse were working on was whether changes in the attitudes of individual donors may have been responsible for some of the changes in party polarization -- they posit that if individual donors had become increasingly ideological, then it would push candidates to take more ideological positions. I think that's worth looking into, but I think the more promising explanation from the donor side is the possibility that a far greater percentage of all money spent on House and Senate campaigns in recent election cycles is from partisan sources than it was in the 1970s (or perhaps in the 1950s, but campaign finance data doesn't go back that far). I suspect, but don't know for sure, that party networks on both the GOP and Dem side are a lot stronger than they were forty or sixty years ago, and I certainly believe that it's a lot easier for a rank-and-file donor to learn about marginal Congressional races and act on that knowledge than it was until very recently. At any rate, it sure seems to me that the first step is to get a good handle on party moneys in contemporary elections, and unfortunately I don't think we're there yet.
(I should mention as always that I have lots of friends and professional acquaintances doing work in this area: Ray and Casey are both my friends, as are plenty of others working on money in politics and most of those working on party networks).