Well, at least this is what two people on this website believe.
Just because an alleged attempt was made, does not imply that the attempt was successful.
For example, if the software were written such that if 150 thousand votes had been tablulated, each 10,000 democratic vote causes the total Democratic votes to be multiplied by 1.15 (up 15%), while each 10,000th vote by the Republicans causes the total Republican votes to be multiplied by 0.85 (down 15%).
This number would be high enough such that only an intensive (ie. non-humanly verifieable) testing method would catch it; and the total numbers at the end of the night would make 'sense' with the recorded number of voters.
Perhaps President Bush 'really' won 68% of the total vote, instead of 51%.