Three states’ electoral votes in 2008 were won with less than a majority and with at least one third-party/independent candidate having more votes than the margin between the top two. One other state was likewise won with less than a majority, with two candidates combining for more than the margin.
Won by Obama with 49.92% over McCain’s 48.96%
Obama margin over McCain: 26,163
Bob Barr: 29,196
Won by McCain with 49.44% over Obama’s 49.24%
McCain margin over Obama: 5,868
Ralph Nader: 17,769
Bob Barr: 11,355
Chuck Baldwin: 8,181
(Cynthia McKinney: 958)
Won by McCain with 49.66% to Obama’s 47.16%
McCain margin over Obama: 12,136
Ron Paul: 10,499
Ralph Nader: 3,570
Bob Barr: 1,300
Won by Obama with 49.70% over McCain’s 49.38%
Obama margin over McCain: 13,692
Bob Barr: 25,408
It is very likely that votes for Ralph Nader (at 3.03 times the margin) cost Obama the electoral votes of Missouri and that votes for Bob Barr (at 1.86 times the margin) cost McCain the electoral votes of North Carolina. As for Montana and Indiana, as well as the vote totals of Barr and Baldwin in Missouri, because I will not assume that all Barr/Baldwin/Paul votes would have gone to McCain or all Nader/McKinney to Obama, it is harder to say, but an affect on the outcome is certainly possible.
Fortunately, the choice of President did not hinge on these states. But it is well past time that we did away with the electoral college and plurality voting.
Source: Dave Leip, with an assist from good old Wikipedia (where, unlike at Leip or the media sites I checked, someone bothered to enter the individual candidate totals for candidates not named McCain or Obama.)