I do not undestand it. If they were REALLY interested in getting elected, they would do it the way every normal person in this country would - by building their local base by being elected to local and state legislature, then perhaps governorship, then congress or senate, etc. Focusing on presidency at this stage of the game is trurning things on their head and an utter waste of time, effort, and resources. That seems to suggest that these folks are either too stupid to understand the political process, or have some hidden agenda. Either case disqualifies them as serious candidates.
OTOH, if one accepts that elections in this country is meaningless popularity contest that has minimal impact on the management of the country, then running a symbolic candidate could make some sense, if only as a travesty.
BTW, I voted for Nader in 2000 as a part of the Nader-Trader scheme.
Wojtek