At the time the Affordable Health Care for America Act passed, there was much speculation that a "yes" vote might put Democratic House members from moderate and conservative districts in greater danger of electoral defeat. Political science research on congressional elections tells us that voters are known to punish members of Congress for being too ideologically out of step with their districts, but would one particular roll call vote matter?
It certainly seems that a number of Democratic members thought so. In North Carolina, the Democratic members in the most conservative districts - Heath Shuler, Larry Kissell and Mike McIntyre - all voted against the health care bill.
Now, six months after President Barack Obama signed the landmark bill into law, the Republican Party, in its Pledge to America, has vowed to repeal parts of it. But with ongoing economic troubles, the issue of health care seems to have substantially faded from political consciousness. Has the health care vote had any lasting negative effects on Democrats running for re-election in more conservative districts?
To see how House members in these districts were faring, we looked at the current election forecasts created by fivethirtyeight.com and The New York Times. We focused on members from the 50 most conservative congressional districts that are represented by Democrats.
Of these 50 districts, only 41 had members who cast a vote on health care reform and are currently running for re-election. Dividing these members into two groups based on their health care votes, those who voted for health reform are running 2.7 percentage points behind those who voted against it.
Of course, there are a number of other factors, such as the members' own ideology and the liberal or conservative tendency of their districts, which might explain this difference. We therefore estimated a statistical model that controlled for the ideology of the members and the ideology of the district.
Our results from this more sophisticated analysis further bolster the case that voting in favor of health care created lasting damage for Democratic members in conservative districts. With our controls, we found statistically significant evidence that Democratic supporters of health care reform are running just over 3 percentage points behind Democrats who opposed the bill.
Typically, of course, most members of Congress running for re-election win by much greater margins than 3 percent, but this is not a typical midterm election. In 2010, for Democratic incumbents from conservative districts in a distinctly anti-Democratic year, 3 points is serious business. Indeed, of the 41 Democrats we examined, only six are forecast to win by more than 3 points - and none of those voted for health care reform.
In truth, most voters probably do not have a clear idea of how their member of Congress voted on the health care bill and are rather largely focused on the state of the economy. However, the vote has clearly created a dynamic that has disadvantaged reform supporters in conservative districts. A "yes" vote on health reform by a Democrat in a competitive district might have sent a signal to Republicans that this Democrat might be particularly vulnerable. This sign of weakness would have drawn more highly qualified and better-funded Republican challengers, whose stronger campaigns have placed the pro-health reform Democrats at a disadvantage.
Many political forecasters are predicting that the Democrats will lose control of the House in November. This outcome would be driven largely by the state of the economy and by Obama's relative unpopularity. However, the health care vote may determine some of these races at the margins, causing some Democrats who voted for the legislation to go down to narrow defeat.
Of course, if we had robust economic growth, this would all be moot, and even most Democrats in conservative districts would likely be cruising toward re-election, as incumbents typically do. In this atypical year, however, should McIntyre, Shuler or Kissell just barely hang onto his seat, he may have his "no" on health care reform to thank.
Steven Greene is an associate professor in the Department of Political Science at N.C. State University. Seth Masket holds a similar post at the University of Denver.