If you hoping for (or dreading) indications of a clear shift in voter preferences on the surveys released in the last 24 hours, you will not find them here this morning. As of this writing, Barack Obama's margin has clicked up very slightly on our national trend estimate, while yesterday's statewide surveys show a very slight narrowing of that margin in a few key battleground states. However, our current classification of the states remains unchanged over the weekend: We still show 311 electoral votes for Obama, 142 for McCain with seven states representing 85 electoral votes still in our toss-up category.
One big caveat: We will no doubt see a heavy pace of new statewide and national survey releases later this morning. Some will be released by the time you read this. I am planning to do another update at the end of the day to summarize the final round of polls.
At the state level, we logged in 25 new surveys yesterday, of which 15 tracked previous polls by the same pollster released since October 15. Of these 15 tracking polls, 11 showed small nominal shifts toward McCain, 2 showed nominal shifts to Obama and 2 showed no change in margin.
The impact of these new surveys on our trend estimates is very slight. We do show slight shifts on the margins of our trend estimates to McCain in more states (8) than to Obama (4) but these changes mostly represent a few tenths of a percentage point. The average shift across all of the battleground states since Sunday is just 0.1% to McCain.
Four new survey releases in Pennsylvania confirm that Obama's lead there has narrowed significantly over the last week, although four polls still show Obama leading by margins of 6 to 8 percentage points, with Obama receiving more than 50 percent of the vote. Even if the McCain campaign is counting on the typical "Bradley Effect" (in which most or all undecided voters "break" to the white candidate), Obama's 51.8% of the vote on our trend estimate indicates that McCain would still fall short.
In Virginia, two new automated surveys from SurveyUSA and PPP both show Obama leading (by margins of 4 and 6 percentage points respectively), although by slightly narrower margins for Obama since last week. Our trend estimate shows Obama leading by 6.3 points (50.6% to 44.3%), still a big enough margin to qualify as "leaning" Obama.
Three new surveys in Ohio show a similar pattern. The new automated telephone survey from PPP and the mail survey from the Columbus Dispatch shows Obama leading by 2 and 6 points respectively, while a new live interviewer survey from Mason-Dixon shows Obama trailing by two percentage points. The new surveys narrow to 5.6 points (49.9% to 44.3%), just enough to remain in the "lean" Obama category.
Ohio is one state where Obama's margin has been consistently narrower on automated IVR surveys (+1.5 percentage points as of this writing) than on live interviewer telephone surveys (+5.8 points). Here too, the difference is mostly in McCain's percentage of the vote. As of this writing, Obama receives 48.7% of the vote on our trend estimate if based only on automated surveys and 49.3% if based only on live interviewer surveys.
I will have more to say about the final round of national polls later, but for now let me underscore yesterday's warning about the danger's of cherry-picking. The pace of releases and the not entirely comparable field dates make apple-to-apple trend comparisons difficult, but the table above obviously shows shifts in McCain's direction on some surveys (as compared to their most recent sample with non-overlapping field dates), and shifts to Obama on others. With the exception of the outlying IBD/TIPP survey, Obama's leads by comfortable margins on all of these final or nearly final polls. Four years ago, George Bush held a average 1.5 percentage point lead on the final round of national polls. Obama's lead on these 12 surveys averages 7.3 points -- virtually the same margin (7.2) that he receives on our overall national trend estimate as of this writing.
Charles Franklin's graphic posted last night is probably the best way to look for late trends in the national tracking polls. As of last night, eight trackers were showing Obama's margin increasing and two decreasing, but as Franklin points out "three or four of the rises are quite small."