The Obama campaign has invested quite a bit of energy in promoting early voting, so it probably gave Democrats heart palpitations on Monday when Gallup released a poll showing Mitt Romney with a big lead among those who’ve already cast ballots.
At first blush, with about 15% of the total numbers of votes already cast, these figures would suggest Romney is on his way to a significant victory next week. Indeed, Dave Weigel noted yesterday that the early-vote calculation “looks terrible” for President Obama’s re-election prospects.
But there’s another angle to consider: Gallup’s numbers look at the national picture, and by all appearances, the election will come down to the key battleground states. Jon Walker had a good piece on this:
[I]n the important swing states Obama holds a big lead in the early vote. In Nevada and Iowa significantly more Democrats than Republican have voted already. Similarly, polling in Ohio shows Obama leads 63% to 36% among people who have voted.
I often think of the national polling like a “control group” in an election experiment. It is only in the swing states that the campaigns are really active. By comparing what happens in the swing states to what is happening in the non-swing states, you can try to separate broad trends from what is actually being accomplished by the physical campaigns.









