Where Voters "Matter"

In today's WSJ, Gerald Seib writes:

The most exhilarating campaign of our time has come to an end, and some 130 million Americans now will put the exclamation point at the end of that sentence by casting votes. Each of those votes is equal, of course, but some are more equal than others.
That is, some votes have more strategic significance. They will determine whether Sen. John McCain can pull off a surprise, or whether Sen. Barack Obama wins by a small margin or with a mandate.

His piece is a nice, concise look at the states that may determine the election.