Andrew Gelman takes me to task for what I said about the electoral college last week, pointing out that he's established that small-state voters are much more likely to be the tipping-point vote than large state voters.
I'm aware of the finding, but I disagree with the interpretation. I don't think the question of whether a voter in a particular state has a better chance of tipping the election -- the question which Gelman's articles consider -- is the same question as whether that state has an electoral college advantage. It's a piece of it, but not, I don't think a very important one.
The question of individual voter power looks at it from the point of view of the individual voter. What we want, however, is to look at it from the point of view of the campaigns. What matters there is whether there are differences between states linked to size. As I said earlier, it used to be the case that big, urban states tended to be closer than the smaller, rural states. That seems to be less true now, but I it's still somewhat the case. Let's see...in 2008, there were 18 states with a total of 101 electoral votes that were 20 points or more from the national average (in other words, Republican states where McCain won by at least 13 and Democratic states where Obama won by 27 points or more). That's an average of 5.6 electoral votes in the least competitive states. What about the closest states, those within 10 points of the national average? There are 19 of those...with a whopping 221 electoral votes, for an average of 11.6 per state.
Conclusion: if you go after close states, you'll be going after big states. And so, overall, the big states tend to have an advantage, over and above the advantage that their size alone would give them in a direct vote system.
Moreover, it's probably not just a random effect, but built into the electoral college system. For one thing, it's probably true that larger states are less homogeneous and therefore more likely to be competitive. But more broadly, it makes sense in the long run for parties to chase after big states as units, shifting their policy preferences to try to work those states. It's true, as Gelman says, that the correct comparison point (or at least the one I was working from in the original post) is to a direct vote system, and the large numbers in big states would of course get attention in that system as well. However, this is where the points made in the comments to Gelman's points come in. Looking ahead in the long run, it's probably a lot easier for a party to target big, potentially close states and ignore the little ones, all things being equal. Granted, things are not necessarily equal: if the same policy could appeal to lots of little states, or if there's no policy that would appeal to a big-state-as-a-whole, then you won't do that.
But the fact that big states strongly tend to be more competitive, and the fact that the effect persists over time, suggests that things are not equal -- things favor the big states.
One more bit of this. To the extent that big states tend to share interests and small states tend to share interests -- something that may or may not be true, but to the extent that it is -- then even the big states that are not competitive may be helped by the electoral college. That is, if New York (not competitive) is similar to Pennsylvania (very competitive), then any policies adopted by the candidates in order to appeal to Pennsylvanians may also help New Yorkers. Again, that's not a sure thing; direct aid to states, for example, wouldn't work that way. And there's also the complication that even if most people in the state have an interest in something, there may be plenty of people who do not, or who disagree with a policy popular elsewhere in the state. But again, on balance this may tend to work in favor of the big states.