More on presidential approval in midterm elections

Two important points of followup on Tuesday's post about how Matt Bai overhyped President Obama's approval rating as "ominous" for Democrats:

1. First, as Emory's Alan Abramowitz correctly pointed out in an email to me, "Seat exposure and the midterm dummy variable predict substantial Democratic losses regardless of what happens to either the generic ballot or Obama approval." See, for instance, Abramowitz's statistical model of House seat swings, which predicts a 38 seat loss for Democrats on the basis of those two factors alone.

2. Second, Rahm Emanuel seems to have bought into the hype about the president's approval rating as the overriding factor in midterms. In Bai's article, he is paraphrased as follows:

For every point that Obama’s approval rating dips below 50 percent, Emanuel said, there are probably four or five more House districts that will swing into the Republican column, and vice versa.

These results are not corroborated by the statistics. Controlling for other factors, Abramowitz's model predicts that a one point decrease in Obama's net approval (approval-disapproval) is associated with a .22 seat shift toward Republicans. (He indicates by email that the coefficient for raw approval is less than 0.5.) Even the simple slope in a bivariate plot is far less than 4-5 seats per point of approval. Unless there's some massive non-linearity around 50% approval, Emanuel's estimate is off by an order of magnitude.

[Cross-posted to Pollster.com]

Comments

[metrichead.blogspot.com]

Brendan - I came across Chris Cillizza's article in the WaPo about the GOP's chances in the Rust Belt, and I have an interesting question you might have an answer for.

Whenever Presidents' popularity slips in the first two years and we see more states electing governors of the opposing party. Does that effect mirror state governors in presidential election years where their popularity declines and helps the incumbent?

[metrichead.blogspot.com]

Bah, sorry.

http://www.washingtonpost.com/wp-dyn/content/article/2010/06/20/AR2010062003006.html?hpid=topnews

[bnyhan]

Not sure I understand the second paragraph -- are you asking whether the president's approval rating is correlated with governors, or whether the economy affects gubernatorial approval ratings, or what?

[metrichead.blogspot.com]

I'm asking if there's a correlation between a President and a state Governor's popularity in off-year elections.

Clinton, a Democrat wins in 1992, loses the House and Senate in 1994; here in Michigan, John Engler, a Republican, carried the state for Governor in '94. In 1996, Clinton carried Michigan, despite Engler's victory two years prior. Do Governors like Engler of the opposition party suffer losses of support in off-year elections (i.e. Presidential election years) which helps the incumbent President?