The Gallup Poll's Bouncing "Generic" Ball

09/09/2010 03:00 pm ET | Updated May 25, 2011

Anyone following campaigns closely has seen the numbers and read the stories. Democrats are in trouble. One particularly salient point: last week's Gallup tracking poll showing a +10 advantage for Republicans in the generic ballot test. It's the largest Republican advantage in the history of Gallup asking the question. Some calculated what a +10 advantage would mean as far as seat pickup. Others simply rejoiced.

But hold on! Yesterday Gallup released its latest generic ballot test. It's evenly split between Dems and Republicans. We're coming back! Obama's address on Iraq had an effect! Glenn Beck's rally had an effect! Sound the other alarm now! Huh, I guess I missed those stories.

To be sure, Democrats are in trouble. To be sure, according to's tracking, the generic ballot is trending Republican when you aggregate all polling outlets. But why is one poll (+10) covered so extensively, while another (+0) hardly at all? Why is the former considered important, and the second, perhaps an outlier? This new data point is receiving far less coverage. (Media Matters has a very good summary of the difference in coverage here.)

It's hard to know exactly what is causing the fluctuation--whether it's simple poll fluctuation, or "real" movement. But looking at Gallup's breakout of the generic by party, we see most of the movement comes from Democrats consolidating the base. In the current poll, 93% of self-identified Democrats say they are voting for the Democratic candidate, up from 88% in the previous wave. Republican support for the Republican candidate dropped just slightly (96% to 93%). The difference in base consolidation is now even, for the first time in a month. The chart below shows this metric since Gallup began nightly tracking in March.

Generic Ballot

That remaining Democratic holdouts would begin to come home as we head into the final stretch is not a surprise. Will this pattern hold, and how it translates into actual House seats, remains to be seen. But for those following campaign twists and turns, the latest Gallup poll is a twist worth a bigger mention.