Actually, the way delegate allocation is, it quite possibly could. Let's take Virginia for example. Let's say it is very close with Obama winning by 4 and Goode gets 5% of the vote. If Virginia goes winner take all, even a small single digit take by Goode could give Obama those delegates. The closer the race, the more third party candidates can change the outcome (talk to Nader and Gore about Florida).
In this case, Virginia becomes a swing state. In New York or California, for example, you can vote and campaign for Romney until the cows come home and the entire electoral college will still go to B.O. A third party vote in a CLEARLY non swing state won’t affect anything. Just saying...