Although I have not seen Tuesday’s data yet (and can’t for some time because of a speaking engagement), enough is known to allow some advance comments. Bottom line: not only is there no bounce so far, the data suggest the possibility of a negative bounce. Update, 12:35pm: yep, there it is. ~10 EV and counting…
The story follows…
The Meta-margin above is interpreted just the same way as a regular margin. Calculated using all available state polls, it is defined as how much opinion would have to swing to create an electoral near-tie. As you can see, opinion this year has stayed within a narrow range. The Meta-margin standard deviation (MMSD) has been about 1.0 percentage point. To put it another way, the Democratic-Republican margin has spent two-thirds of its time in a 2.0-point range. If the range is an indication, as many as 98-99% of us are certain of who we want as President (with 51% for Obama). In this context, the 3-point Ryan VP bounce I reported was impressive — but was not enough to flip the race.
This is an extreme situation. In 2004 and 2008, the MMSD was about 2.5 percentage points, typical of a re-election race (which 2004 was). This year it’s less than half of that, reflecting a very decided and/or polarized electorate.
In the first post-convention change, on Monday the Meta-margin moved towards Obama by a fraction of a point. Is this a small fluctuation…or is it the start of an “inverse” bounce? We will know more by later today (updates occur at 8AM, noon, 5PM, and 8PM). An inverse bounce might reflect the public response to the GOP convention, which ranged from tepid to dismal. It’s not great for the nominee to be overshadowed by an empty chair.
What will happen this week as a result of the Democratic convention? Look again at both the Meta-margin (above) and this year’s EV Meta-analysis:
Given the narrow range so far, any post-Democratic convention bounce is likely to be small. I expect the Meta-margin and EV estimator to stay below a ceiling of 4.0% and 320 EV, respectively. A bounce that exceeds those limits would be a noteworthy event.
However, as I’ve written before, all of this is of no import to the Presidential race. Based on polls and likely future movement, a low-assumption calculation gives President Obama’s re-election probability as 88%. That could change, but not because of convention bounces, which don’t last.
Far more important are the Senate and the House, where party control is on a knife’s edge. A lasting shift in the race, whether from the conventions or another source, will mean the difference in 2013 between divided government and single-party control of the Presidency and Congress. Control of Congress is a big story of the campaign, and a source of real suspense. In the coming weeks, I hope more pundits will notice.