Last night's update of our Slate Election Scorecard feature notes a big change (also reflected on our new Pollster map and scorecard): Republican George Allen's margin over Democratic challenger Jim Webb has narrowed to the point that we now rate Virginia as a toss-up. Thus, for the first time in the campaign, Democrats have an overall lead: 49 seats are currently held by Democrats or at least lean that way, 48 lean or are held by Republicans. To win control of the Senate, Democrats will need to win two of the three toss-up states: Missouri, Tennessee and Virginia.
A few additional notes about the new surveys in Virginia and Missouri:
Virginia shifted to toss-up as a result of a new LA Times-Bloomberg poll that had Webb leading by a statistically insignificant three points (47% to 44%). Since Slate posted our update, SurveyUSA released another poll showing Allen leading by three (49% to 46%). Even though the new poll has Allen slightly ahead, it replaces an outlier Zogby poll from early October that had Allen ahead by 11 (48% to 37%) and will serve to narrow Allen's lead even further on our last-five-poll average. Tomorrow's update will show Allen's margin on our summary table shrinking to only 1.8% (47.6% to 45.8%).
The Slate update also discusses two new polls in Missouri from LA Times/Bloomberg and SurveyUSA that suggest new momentum for Republican Senator Jim Talent in Missouri. Both surveys show Talent ahead by a statistically insignificant three points, but previous surveys had shown Democrat Claire McCaskill ahead by similar margins. The net result on our last-five poll average remains very close race that still easily qualifies as a toss-up.
While the small shift to Talent may well be real, poll consumers ought to keep in mind two words when it comes to surveys conducted in Missouri the week: World Series.
The World Series gives pollsters fits, especially when we have to poll states with a hometown team -- like the St. Louis Cardinals -- playing for all the marbles. The games draw huge audiences in the home markets of the contenders, and no one wants to stop watching the game to complete a telephone survey. As a result, pollsters typically experience lower response rates, particularly among younger men. Complicating all of this even further in Missouri is the high-profile exchange of television advertisements on stem cell research that aired during the World Series gaemes (an ad on behalf of Claire McCaskill featuring Michael J. Fox and a response by the Cardinals' Jeff Suppan and actors Patricia Heaton and Jim Caviezel).
What effect any of this might be having on the Missouri results (or whether it has had any effect at all) is a matter of pure speculation. However, I can tell you that some of the screwiest internal polls I have seen in my career were fielded during past World Series. So perhaps a few more grains of salt than usual are in order this week.