Newsweek has a new poll taken 6/18-19/07 that finds approval of President Bush at 26%, disapproval at 65%. With this new data point the approval trend estimate stands at 29.9%, the first time the trend has fallen below 30%. The sharpness of the decline is striking. The change-point for approval is April 23, corresponding to the week of the Congressional vote for deadlines and a fund cutoff in Iraq and the President's subsequent veto. It precedes the immigration debate, though that debate may have sustained the decline. (On the other hand there is little evidence that immigration accelerated the decline which was already underway.)
A look at the last six polls is revealing. Newsweek usually has a "house effect" of about 2.2 percentage points below the trend estimate, so finding it below trend is no surprise. But look also at NBC/WSJ. Their house effect has been around -.6, only a shade below trend. But the new NBC/WSJ poll 6/8-11/07 found approval at 29%. And Gallup's house effect is +.55, and their latest reading was 32%. That makes it awfully convincing that approval has now fallen to very nearly 30%, plus or minus 1. (And to reiterate one more time, house effects incorporate many effects that are specific to a given polling organization. These include how don't knows are treated (are people pushed to respond), question wording, sample selection and non-response rates and order of questions within a survey.)
Given that agreement among polls, it is not surprising that the outlier analysis finds nothing to complain about. The confidence interval around the trend estimate is approximately +/- 5%, so Newsweek at -3.9% is well within that range.
The trend over the last 20 estimates has been unrelentingly downward. Despite the long stability in approval from December through mid-April, the trajectory of approval has been dramatically down since April 23.
Newsweek headlines "How low can he go?" We looked at that a while back in this post. One of the keys I pointed out then was the support presidents enjoy from their own supporters. Past unpopular presidents have suffered a substantial loss of support from their party. President Bush has been a significant exception to this. His lows among Democrats and independents have not been accompanied by similar declines among Republicans. When the post was written in March 2006 approval stood at 38%. Approval among Democrats was 10% back then while independents reported 27% approval. These were much lower than history would predict for a president at 38%. The huge difference was that Republican support in March 2006 was an amazing 82%.
That support has been slipping in recent months. The Newsweek poll finds approval at 6% among Democrats, 23% among independents and 60% among Republicans. The GOP partisans still are providing more support than we might expect, but it is clearly no longer the reservoir of support it once was. (Gallup now finds Democrats at 8%, independents at 24% and Republicans at 73%. Since the historical analysis reported above was based on Gallup polling, a fair comparison would be the shift from 82% in March 2006 to 73% now among Republicans, a less dramatic comparison, but one that still demonstrates the strains on Republican support. It also casts some light on differences between polling organization results.)
Because approval among Democrats is so low, further declines there can make little difference to the overall level. Independents could matter a bit more, but how low approval ultimately goes is going to depend on Republicans' willingness to continue to stand by the president.
