Most states give their electoral votes using a rule of "winner- take-all." In this method, the candidate who wins the most popular votes in the state gets all of its electoral votes. This is true even if the candidate wins by only a small margin. As a result, a change in a small number of votes can make a big difference. In the election of 2000, for instance, one candidate or the other won six states by fewer than 10,000 votes each. Two of those states, worth 30 electoral votes, were won by fewer than 600 votes.