See here for what they're up to in Ohio.
And, while that's going on, McCain is now publicly raising the issue that "voter fraud" could cost him Florida. See here for his comments on TV.
So, it's shaping up as a big one-two punch. In key battleground states, reduce voters likely to vote for Obama + raise the "alarm" about voter fraud = a very close race Republicans may win or at least one they can litigate to a win.