So I wrote  about the Biden pick by Obama and opined that it was so poorly done in execution and substance that any bounce would be gone by Sunday. When Sunday  arrived, the first post-Biden pick poll confirmed my suspicion. Today, we got another nail in the coffin. Bithead  has already remarked on the poll, but I want to go into a bit more depth.
The Gallup  tracking poll takes a daily poll of 1000+ likely voters and then combines them every day for a three day running total. So they take the latest day, throw out the oldest day and re-average every day. Starting with the Monday before the announcement, the tracking poll numbers look like this:
Obama 45 45 45 45 46 45 45 44
McCain 44 43 44 44 44 45 45 46
So the Friday before the pick, Obama was ahead 46 to 44, the first day of the pick, Saturday, the poll goes back to tied. The second day, it remains tied. The third day, Monday, McCain takes the lead. Now given that the three days before the announcement, Obama was tied or had a lead. This means to go back to tied, he had to have a “bad Saturday” to move the two point poll advantage from Friday. Further, once we got the Friday numbers out of the three day track, we get to see McCain take a two point lead.
Recognize that the polls have been showing Obama and McCain statistically tied for the last week and a half. So it is to early to tell if this is just statistical wobble or a harbinger of meaning something. Plus, it would be a polling anomaly for the democratic convention to have no bounce, no matter how small or how short lived. So we would expect the polls to come back down as the convention gets factored in. But this snapshot indicates that isolating the Biden pick, it certainly didn’t help (assuming the change is just statistical wobble) and it may have hurt. If McCain maintains or widens his lead over the next several days, despite the convention, then we will know that Obama’s pick was only to be matched by the McGovern-Eagleton selection. And given that Obama has a lot of McGovern’s far left tendencies, it may be something in the far left mindset that selectes VP’s who turn out to be a drag on the ticket.