How much is health care hurting the Democrats?

01/21/2010 10:06 am ET | Updated May 25, 2011

Via John Sides, David W. Brady, Daniel P. Kessler, and Douglas Rivers have published an op-ed in the Wall Street Journal that is likely to fuel Democratic panic in Washington over health care:

The majority party normally loses seats in midterm elections, but the Republican resurgence of recent months is more than a conventional midterm rebound. How can a little known Republican run a competitive Senate campaign in Massachusetts? The culprit is the unpopularity of health reform, and it means that Democrats will face even worse problems later this year in less liberal places than Massachusetts.

We have polled voters in 11 states likely to have competitive Senate races in November on how they feel about health reform and how they might vote in November...

Health reform is more popular in some of these states than in others. Where it's popular, Democratic candidates don't have too much of a problem, but where it's unpopular--and that includes most states--the Democratic Senate candidates are fighting an uphill battle...

Support for the Republican Senate candidates in these races is closely related to voter opposition to the health-care Senate bill...

How do we know that it's the health-reform bill that's to blame for the low poll numbers for Democratic Senate candidates and not just that these are more conservative states?

First, we asked voters how their incumbent senator voted on the health-care bill that passed on Christmas Eve. About two-thirds answered correctly. Even now, long before Senate campaigns have intensified, voters know where the candidates stand on health care. And second, we asked voters about their preference for Democrat versus Republican candidates in a generic House race. As in the Senate, the higher the level of opposition to health reform, the greater the likelihood that the state's voters supported Republicans.

Brady and Rivers are highly respected political scientists (I'm not familiar with Kessler), but I'm not sure we can draw strong conclusions from these data. Since health care passed on a perfect party line vote in the Senate, it's relatively easy to know where an incumbent stands on the issue. And given the salience of the health care debate, the correlation between state opposition to health care reform and support for Republican senate candidates is (a) not surprising and (b) not necessarily causal (especially given that those are aggregate measures).

I tend to think that much of the health care fallout is an expression of economic discontent, but there's certainly an argument to be made that it has exacerbated the public's predictable turn away from liberalism. In either case, however, disentangling these factors is extremely difficult.

Update 1/21 8:25 PM: Matt Blackwell makes a similar argument at the Harvard Social Science Statistics blog.