Nate Silver and the rest of the 538.com crew have just finished thoroughly eviscerating the Republican polling firm Strategic Vision. There have been a number of less serious anomalies with Rasmussen as well (though Rasmussen had an excellent record with the 2006 and 2008 races). And not too long ago, Stu Rothenberg was caught mouthing GOP talking points about the race in NY-20. Rothenberg has also made a number of other comments (here; here) that make it clear he leans Republican personally.
So here’s something interesting: Rothenberg is currently predicting a small number of losses for Democrats in the House (it looks like a dozen or less from this) while Charlie Cook says there’s a 50-50 chance that Democrats will lose 40 or more (Rothenberg, by contrast, shows only a total of 31 Democratic seats as being at all in play and most of these he ranks as relatively safe).
I find the intersection of political prognosticating and political messaging to be a fascinating place. I think that most of the major prognosticators (Cook, Rothenberg, Sabato — with obvious local exceptions, previously Chuck Todd) play it straight with their predictions (if not their other comments) for the simple reason that to do otherwise would hurt them professionally. But politics is full of self-fulfilling prophecies, people like to back a winner, fundraising depends on the perception of how likely a candidate is to win a race, and so on. There’s an interesting tension between trying to accurately predict things (as, say, Carville/Greenberg’s Democracy Corps group does or, be bipartisan here, Mike Murphy generally does) and saying crazy stuff about having “the math” that you think will help your side win.
I often wonder what someone like Michael Barone thinks he’s accomplishing by spewing right-wing nonsense when he could be using his former respectability to further his political agenda.