The first set of numbers is the general presidential tracking poll. The second is restricted to 11 swing states (with 146 electoral votes).
Romney's number is the same in both places, and Obama snags an extra 3% when you look at the whole country. In the general group, there are 6% that go to neither candidate, and that's evenly divided between undecideds and people who are voting for some other candidate. In the swing states, you've got 9% who aren't (yet) going for Obama or Romney, and within this group 4% go to some other candidate and 5% are undecided.